We derive an N-fold Darboux transformation for the nonlinear Schrdinger equation coupled to a multiple selfinduced transparency system, which is applicable to optical fiber communications in the erbium-doped medium.Th...We derive an N-fold Darboux transformation for the nonlinear Schrdinger equation coupled to a multiple selfinduced transparency system, which is applicable to optical fiber communications in the erbium-doped medium.The N-soliton, N-breather and N th-order rogue wave solutions in the compact determinant representations are derived using the Darboux transformation and limit technique. Dynamics of such solutions from the first-to second-order ones are shown.展开更多
Recent years have witnessed significant advances in utilizing machine learning-based techniques for thermal metamaterial-based structures and devices to attain favorable thermal transport behaviors.Among the various t...Recent years have witnessed significant advances in utilizing machine learning-based techniques for thermal metamaterial-based structures and devices to attain favorable thermal transport behaviors.Among the various thermal transport behaviors,achieving thermal transparency stands out as particularly desirable and intriguing.Our earlier work demonstrated the use of a thermal metamaterial-based periodic interparticle system as the underlying structure for manipulating thermal transport behavior and achieving thermal transparency.In this paper,we introduce an approach based on graph neural network to address the complex inverse design problem of determining the design parameters for a thermal metamaterial-based periodic interparticle system with the desired thermal transport behavior.Our work demonstrates that combining graph neural network modeling and inference is an effective approach for solving inverse design problems associated with attaining desirable thermal transport behaviors using thermal metamaterials.展开更多
We theoretically investigate the magnomechanically induced transparency phenomenon,Fano resonance and the slow-fast light effect in the situation where an atomic ensemble is placed inside the hybrid cavity of an optom...We theoretically investigate the magnomechanically induced transparency phenomenon,Fano resonance and the slow-fast light effect in the situation where an atomic ensemble is placed inside the hybrid cavity of an optomagnomechanical system.The system is driven by dual optical and phononic drives.We show double magnomechanically induced transparency in the probe output spectrum by exploiting the phonon-photon coupling strength.Then,we study the effects of the decay rate of the cavity and the atomic ensemble on magnomechanically induced transparency.In addition,we demonstrate that effective detuning of the cavity field frequency changes the transparency window from a symmetrical to an asymmetrical profile,resembling Fano resonances.Further,the fast and slow light effects in the system are explored.We show that the slow light profile is enhanced by adjusting the phonon-photon coupling strength.This result may have potential applications in quantum information processing and communication.展开更多
Electrical energy is essential for modern society to sustain economic growths.The soaring demand for the electrical energy,together with an awareness of the environmental impact of fossil fuels,has been driving a shif...Electrical energy is essential for modern society to sustain economic growths.The soaring demand for the electrical energy,together with an awareness of the environmental impact of fossil fuels,has been driving a shift towards the utilization of solar energy.However,traditional solar energy solutions often require extensive spaces for a panel installation,limiting their practicality in a dense urban environment.To overcome the spatial constraint,researchers have developed transparent photovoltaics(TPV),enabling windows and facades in vehicles and buildings to generate electric energy.Current TPV advancements are focused on improving both transparency and power output to rival commercially available silicon solar panels.In this review,we first briefly introduce wavelength-and non-wavelengthselective strategies to achieve transparency.Figures of merit and theoretical limits of TPVs are discussed to comprehensively understand the status of current TPV technology.Then we highlight recent progress in different types of TPVs,with a particular focus on solution-processed thin-film photovoltaics(PVs),including colloidal quantum dot PVs,metal halide perovskite PVs and organic PVs.The applications of TPVs are also reviewed,with emphasis on agrivoltaics,smart windows and facades.Finally,current challenges and future opportunities in TPV research are pointed out.展开更多
Mechanically durable transparent electrodes are essential for achieving long-term stability in flexible optoelectronic devices.Furthermore,they are crucial for applications in the fields of energy,display,healthcare,a...Mechanically durable transparent electrodes are essential for achieving long-term stability in flexible optoelectronic devices.Furthermore,they are crucial for applications in the fields of energy,display,healthcare,and soft robotics.Conducting meshes represent a promising alternative to traditional,brittle,metal oxide conductors due to their high electrical conductivity,optical transparency,and enhanced mechanical flexibility.In this paper,we present a simple method for fabricating an ultra-transparent conducting metal oxide mesh electrode using selfcracking-assisted templates.Using this method,we produced an electrode with ultra-transparency(97.39%),high conductance(Rs=21.24Ωsq^(−1)),elevated work function(5.16 eV),and good mechanical stability.We also evaluated the effectiveness of the fabricated electrodes by integrating them into organic photovoltaics,organic light-emitting diodes,and flexible transparent memristor devices for neuromorphic computing,resulting in exceptional device performance.In addition,the unique porous structure of the vanadium-doped indium zinc oxide mesh electrodes provided excellent flexibility,rendering them a promising option for application in flexible optoelectronics.展开更多
A graphene-based metamaterial with tunable electromagnetically induced transparency （EIT）-like transmission is nu- merically studied in this paper. The proposed structure consists of a graphene layer composed of cou...A graphene-based metamaterial with tunable electromagnetically induced transparency （EIT）-like transmission is nu- merically studied in this paper. The proposed structure consists of a graphene layer composed of coupled cut-wire pairs printed on a substrate. The simulation confirms that an EIT-like transparency window can be observed due to indirect cou- pling in a terahertz frequency range. More importantly, the peak frequency of the transmission window can be dynamically controlled over a broad frequency range by varying the Fermi energy levels of the graphene layer through controlling the electrostatic gating. The proposed metamaterial structure offers an additional opportunity to design novel applications such as switches or modulators.展开更多
A reflection-type electromagnetically induced transparency（EIT） metamaterial is proposed, which is composed of a dielectric spacer sandwiched with metallic patterns and metallic plane. Experimental results of THz ti...A reflection-type electromagnetically induced transparency（EIT） metamaterial is proposed, which is composed of a dielectric spacer sandwiched with metallic patterns and metallic plane. Experimental results of THz time domain spectrum（THz-TDS） exhibit a typical reflection of EIT at 0.865 THz, which are in excellent agreement with the full-wave simulations. A multi-reflection theory is adopted to analyze the physical mechanism of the reflection-type EIT, showing that the reflection-type EIT is a superposition of multiple reflection of the transmission EIT. Such a reflection-type EIT provides many applications based on the EIT effect, such as slow light devices and nonlinear elements.展开更多
A kind of photonic crystal structure with modulation of the refractive index is investigated both experimentally and theoretically for exploiting electromagnetically induced transparency（EIT）.The combination of EIT ...A kind of photonic crystal structure with modulation of the refractive index is investigated both experimentally and theoretically for exploiting electromagnetically induced transparency（EIT）.The combination of EIT with periodically modulated refractive index medium gives rise to high efficiency reflection as well as forbidden transmission in a threelevel atomic system coupled by standing wave.We show an accurate theoretical simulation via transfer-matrix theory,automatically accounting for multilayer reflections,thus fully demonstrate the existence of photonic crystal structure in atomic vapor.展开更多
A graphene-based metamaterial for THz plasmon induced transparency(PIT) is presented and numerically studied in this paper, which consists of two horizontal graphene strips attached to a continuous vertical wire separ...A graphene-based metamaterial for THz plasmon induced transparency(PIT) is presented and numerically studied in this paper, which consists of two horizontal graphene strips attached to a continuous vertical wire separately. The calculated surface current distributions demonstrate that the distinct PIT window results from the near-field coupling of two bright modes. To explore the physical mechanism of PIT effect, we employ the coupled Lorentz oscillator model. The transmission spectra obtained with this model fits well with the simulation results. The performance of the PIT system can be controlled through the geometry parameters of graphene strips. Moreover, the transparency window can be dynamically tuned by varying the Fermi energy and the carrier mobility of the graphene strips. The slow light effect is also explored in our proposed structure and it can achieve 1.25 ps when Fermi energy is 1.3 eV. Finally, the position of the transmission window with the variation of the nearby medium refractive index is examined. Such a proposed graphene-based PIT system may have great potential applications in photonic devices.展开更多
Electromagnetically induced transparency （EIT） is obtained in a symmetric U-shaped metamaterial, which is at- tributed to the simultaneously excited dual modes in a single resonator under lateral incidence. A large ...Electromagnetically induced transparency （EIT） is obtained in a symmetric U-shaped metamaterial, which is at- tributed to the simultaneously excited dual modes in a single resonator under lateral incidence. A large group index accom- panied with a sharp EIT-like transparency window offers potential applications for slowing down light and sensing.展开更多
We study the optical properties of a two-level atomic ensemble controlled by a high-finesse cavity. Even though the cavity is initially in the vacuum state in the absence of external driving, the probe response of the...We study the optical properties of a two-level atomic ensemble controlled by a high-finesse cavity. Even though the cavity is initially in the vacuum state in the absence of external driving, the probe response of the atomic ensemble can be dramatically modified. When the collectively enhanced atom–cavity coupling is strong enough and the cavity decay rate is much smaller than the atomic damping rate, an electromagnetically induced transparency-like coherent phenomenon emerges with a dip absorption for the response of the two-level atoms in the cavity without driving, and thus is called vacuum induced transparency. We also show the slow light with very low group velocity in such an atomic ensemble.展开更多
We have experimentally offset-locked the frequencies of two lasers using electromagnetically induced transparency（EIT） spectroscopy of ^（85）Rb vapor with a buffer gas in a magnetic field at room temperature. The m...We have experimentally offset-locked the frequencies of two lasers using electromagnetically induced transparency（EIT） spectroscopy of ^（85）Rb vapor with a buffer gas in a magnetic field at room temperature. The magnetic field is generated by a permanent magnet mounted on a translation stage and its field magnitude can be varied by adjusting the distance between the magnet and Rb cell, which maps the laser locking frequency to the space position of the magnet. This frequency-space mapping technique provides an unambiguous daily laser frequency detuning operation with high accuracy.A repeatability of less than 0.5 MHz is achieved with the locking frequency detuned up to 184 MHz when the magnetic field varies from 0 up to 80 G.展开更多
We have studied the phenomenon of electromagnetically induced transparency（EIT） of ^87Rb vapor with a buffer gas in a magnetic field at room temperature. It is found that the spectral lines caused by the velocity se...We have studied the phenomenon of electromagnetically induced transparency（EIT） of ^87Rb vapor with a buffer gas in a magnetic field at room temperature. It is found that the spectral lines caused by the velocity selective optical pump effects get much weaker and wider when the sample cell is mixed with a 5-Torr N_2 gas while the EIT signal is kept almost unchanged. A weighted least-square fit is also developed to remove the Doppler broadening completely. This spectral method provides a way to measure the Zeeman splitting with high resolution, for example, the Λ-type EIT resonance splits into four peaks on the D_2 line of ^87Rb in the thermal 2-cm vapor cell with a magnetic field along the electric field of the linearly polarized coupling laser. The high-resolution spectrum can be used to lock the laser to a given frequency by tuning the magnetic field.展开更多
We present a laser frequency locking to Rydberg transition with electromagnetically induced transparency（EIT）spectra in a room-temperature cesium vapor cell. Cesium levels 6S_（1/2）, 6P_（3/2）, and the n D_（5/2）...We present a laser frequency locking to Rydberg transition with electromagnetically induced transparency（EIT）spectra in a room-temperature cesium vapor cell. Cesium levels 6S_（1/2）, 6P_（3/2）, and the n D_（5/2） state, compose a cascade three-level system, where a coupling laser drives Rydberg transition, and probe laser detects the EIT signal. The error signal, obtained by demodulating the EIT signal, is used to lock the coupling laser frequency to Rydberg transition. The laser frequency fluctuation, ~0.7 MHz, is obtained after locking on, with the minimum Allan variance to be 8.9 × 10^（-11）.This kind of locking method can be used to stabilize the laser frequency to the excited transition.展开更多
We study the relationship between electromagnetically-induced transparency（EIT） and Autler–Townes（AT） splitting in a cascade three-level Doppler-broadened system. By comparing the absorption spectrum with the flu...We study the relationship between electromagnetically-induced transparency（EIT） and Autler–Townes（AT） splitting in a cascade three-level Doppler-broadened system. By comparing the absorption spectrum with the fluorescence excitation spectrum, it is found that for a Doppler-broadened system, EIT resonance cannot be explained as the result of quantum interference, unlike the case of a homogeneously broadened system. Instead, the macroscopic polarization interference plays an important role in determining the spectra of EIT and AT splitting, which can be explained within the same framework when being detected by the absorption spectra.展开更多
We study a three-mode double-cavity optomechanical system in which an oscillating membrane of perfect reflection is inserted between two fixed mirrors of partial transmission. We find that electromagnetically induced ...We study a three-mode double-cavity optomechanical system in which an oscillating membrane of perfect reflection is inserted between two fixed mirrors of partial transmission. We find that electromagnetically induced transparency （EIT） can be realized and controlled in this optomechanical system by adjusting the relative intensity and the relative phase between left-hand and right-hand input （probe and coupling） fields. In particular, one perfect EIT window is seen to occur when the two probe fields are exactly out of phase and the EIT window＇s width is very sensitive to the relative intensity of two coupling fields. Our numerical findings may be extended to achieve optomechanical storage and switching schemes applicable in quantum information processing.展开更多
We study the ultraslow optical solitons in a resonant three-level atomic system via electromagnetically induced transparency under a density-matrix （DM） approach. The results of linear and nonlinear optical properti...We study the ultraslow optical solitons in a resonant three-level atomic system via electromagnetically induced transparency under a density-matrix （DM） approach. The results of linear and nonlinear optical properties are compared with those obtained by using an amplitude variable （AV） approach. It is found that the results for both approaches are the same in the linear regime if the corresponding relations between the population-coherence decay rates in the DM approach and the energy-level decay rates in the AV approach are appropriately imposed. However, in the nonlinear regime there is a small difference for the self-phase modulation coefficient of the nonlinear SchrSdinger equation that governs the time evolution of probe pulse envelope. All analytical predicts are checked by numerical simulations.展开更多
The coupled resonator-induced transparency （CRIT） phenomenon, which is analogous to electromagnetically induced transparency in atomic systems, can occur in an original integrated optical resonator system due to the...The coupled resonator-induced transparency （CRIT） phenomenon, which is analogous to electromagnetically induced transparency in atomic systems, can occur in an original integrated optical resonator system due to the coherent interference of the coupled optical resonators. The system was composed of three ring resonators on silicon, each with the same cavity size, and the optical coupling to the input and output ports was achieved using grating with a power coupling efficiency of 36%. A CRIT resonance whose spectrum shows a narrow transparency peak with a low group velocity was demonstrated. The quality factor of the ring resonator can attain a value up to 6x 104, and the harmonic wavelength can be controlled by adjusting the temperature. The through and drop transmission spectra of the resonator are reconciled well with each other and also consistent well with the theoretical analysis.展开更多
We theoretically study optomechanically induced transparency in a spinning Kerr-nonlinear resonator.The interplay between the optical Kerr effect and the Sagnac effect provides a flexible tool for modifying the optome...We theoretically study optomechanically induced transparency in a spinning Kerr-nonlinear resonator.The interplay between the optical Kerr effect and the Sagnac effect provides a flexible tool for modifying the optomechanically induced transparency windows of the signal comparing to the system of a single spinning resonator.It is found that the system will exhibit distinct transparency phenomenon and fast-to-slow light effects.More importantly,a symmetric transparency window appears by adjusting the rotation-induced Sagnac frequency shift to compensate for the Kerr-induced frequency shift.These results open up a new way to explore novel light propagation of optomechanically induced transparency devices in spinning resonators with Kerr nonlinearity.展开更多
A terahertz metamaterial sensor adopting the metamaterial-based electromagnetically induced transparency（EIT） effect is presented for determining the 1,4-dioxane concentration in its aqueous solution. The metamateri...A terahertz metamaterial sensor adopting the metamaterial-based electromagnetically induced transparency（EIT） effect is presented for determining the 1,4-dioxane concentration in its aqueous solution. The metamaterial sensor, which consists of an EIT element unit with a cut-wire metallic resonator and two split-ring metallic resonators fabricated on a 490-μm thick silicon substrate, operates in a transmission geometry. The EIT peak was red-shifted and decreased with the increase of the water volume. A maximum redshift about 54 GHz of the EIT peak was detected between the 1,4-dioxane and water. The presented linear behavior and high sensitivity of the EIT peak depending on the water concentration pave a novel avenue for sensor applications.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11705290 and 11305060the China Postdoctoral Science Foundation under Grant No 2016M602252
文摘We derive an N-fold Darboux transformation for the nonlinear Schrdinger equation coupled to a multiple selfinduced transparency system, which is applicable to optical fiber communications in the erbium-doped medium.The N-soliton, N-breather and N th-order rogue wave solutions in the compact determinant representations are derived using the Darboux transformation and limit technique. Dynamics of such solutions from the first-to second-order ones are shown.
基金funding from the National Natural Science Foundation of China (Grant Nos.12035004 and 12320101004)the Innovation Program of Shanghai Municipal Education Commission (Grant No.2023ZKZD06).
文摘Recent years have witnessed significant advances in utilizing machine learning-based techniques for thermal metamaterial-based structures and devices to attain favorable thermal transport behaviors.Among the various thermal transport behaviors,achieving thermal transparency stands out as particularly desirable and intriguing.Our earlier work demonstrated the use of a thermal metamaterial-based periodic interparticle system as the underlying structure for manipulating thermal transport behavior and achieving thermal transparency.In this paper,we introduce an approach based on graph neural network to address the complex inverse design problem of determining the design parameters for a thermal metamaterial-based periodic interparticle system with the desired thermal transport behavior.Our work demonstrates that combining graph neural network modeling and inference is an effective approach for solving inverse design problems associated with attaining desirable thermal transport behaviors using thermal metamaterials.
基金the financial support of the National Center for Scientific and Technical Research(CNRST)through the‘PhD-Associate Scholarship-PASS’program。
文摘We theoretically investigate the magnomechanically induced transparency phenomenon,Fano resonance and the slow-fast light effect in the situation where an atomic ensemble is placed inside the hybrid cavity of an optomagnomechanical system.The system is driven by dual optical and phononic drives.We show double magnomechanically induced transparency in the probe output spectrum by exploiting the phonon-photon coupling strength.Then,we study the effects of the decay rate of the cavity and the atomic ensemble on magnomechanically induced transparency.In addition,we demonstrate that effective detuning of the cavity field frequency changes the transparency window from a symmetrical to an asymmetrical profile,resembling Fano resonances.Further,the fast and slow light effects in the system are explored.We show that the slow light profile is enhanced by adjusting the phonon-photon coupling strength.This result may have potential applications in quantum information processing and communication.
基金supported by the National Natural Science Foundation of China(Grant number W2432035)financial support from the EPSRC SWIMS(EP/V039717/1)+3 种基金Royal Society(RGS\R1\221009 and IEC\NSFC\211201)Leverhulme Trust(RPG-2022-263)Ser Cymru programme–Enhancing Competitiveness Equipment Awards 2022-23(MA/VG/2715/22-PN66)the financial support from Kingdom of Saudi Arabia Ministry of Higher Education.
文摘Electrical energy is essential for modern society to sustain economic growths.The soaring demand for the electrical energy,together with an awareness of the environmental impact of fossil fuels,has been driving a shift towards the utilization of solar energy.However,traditional solar energy solutions often require extensive spaces for a panel installation,limiting their practicality in a dense urban environment.To overcome the spatial constraint,researchers have developed transparent photovoltaics(TPV),enabling windows and facades in vehicles and buildings to generate electric energy.Current TPV advancements are focused on improving both transparency and power output to rival commercially available silicon solar panels.In this review,we first briefly introduce wavelength-and non-wavelengthselective strategies to achieve transparency.Figures of merit and theoretical limits of TPVs are discussed to comprehensively understand the status of current TPV technology.Then we highlight recent progress in different types of TPVs,with a particular focus on solution-processed thin-film photovoltaics(PVs),including colloidal quantum dot PVs,metal halide perovskite PVs and organic PVs.The applications of TPVs are also reviewed,with emphasis on agrivoltaics,smart windows and facades.Finally,current challenges and future opportunities in TPV research are pointed out.
基金supported by a National Research Foundation of Korea(NRF)grant(No.2016R1A3B 1908249)funded by the Korean government.
文摘Mechanically durable transparent electrodes are essential for achieving long-term stability in flexible optoelectronic devices.Furthermore,they are crucial for applications in the fields of energy,display,healthcare,and soft robotics.Conducting meshes represent a promising alternative to traditional,brittle,metal oxide conductors due to their high electrical conductivity,optical transparency,and enhanced mechanical flexibility.In this paper,we present a simple method for fabricating an ultra-transparent conducting metal oxide mesh electrode using selfcracking-assisted templates.Using this method,we produced an electrode with ultra-transparency(97.39%),high conductance(Rs=21.24Ωsq^(−1)),elevated work function(5.16 eV),and good mechanical stability.We also evaluated the effectiveness of the fabricated electrodes by integrating them into organic photovoltaics,organic light-emitting diodes,and flexible transparent memristor devices for neuromorphic computing,resulting in exceptional device performance.In addition,the unique porous structure of the vanadium-doped indium zinc oxide mesh electrodes provided excellent flexibility,rendering them a promising option for application in flexible optoelectronics.
基金supported by the National Natural Science Foundation of China(Grant No.61307052)the Youth Funding for Science&Technology Innovation in Nanjing University of Aeronautics and Astronautics,China(Grant No.NS2014039)+3 种基金the Chinese Specialized Research Fund for the Doctoral Program of Higher Education(Grant No.20123218110017)the Innovation Program for Graduate Education of Jiangsu Province,China(Grant Nos.KYLX 0272,CXZZ13 0166,and CXLX13 155)the Open Research Program in National State Key Laboratory of Millimeter Waves of China(Grant No.K201609)the Fundamental Research Funds for the Central Universities of China(Grant No.kfjj20150407)
文摘A graphene-based metamaterial with tunable electromagnetically induced transparency （EIT）-like transmission is nu- merically studied in this paper. The proposed structure consists of a graphene layer composed of coupled cut-wire pairs printed on a substrate. The simulation confirms that an EIT-like transparency window can be observed due to indirect cou- pling in a terahertz frequency range. More importantly, the peak frequency of the transmission window can be dynamically controlled over a broad frequency range by varying the Fermi energy levels of the graphene layer through controlling the electrostatic gating. The proposed metamaterial structure offers an additional opportunity to design novel applications such as switches or modulators.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61205096 and 61271066)
文摘A reflection-type electromagnetically induced transparency（EIT） metamaterial is proposed, which is composed of a dielectric spacer sandwiched with metallic patterns and metallic plane. Experimental results of THz time domain spectrum（THz-TDS） exhibit a typical reflection of EIT at 0.865 THz, which are in excellent agreement with the full-wave simulations. A multi-reflection theory is adopted to analyze the physical mechanism of the reflection-type EIT, showing that the reflection-type EIT is a superposition of multiple reflection of the transmission EIT. Such a reflection-type EIT provides many applications based on the EIT effect, such as slow light devices and nonlinear elements.
基金Project supported by the National Natural Science Foundation of China(Grant No.11574188)the Project for Excellent Research Team of the National Natural Science Foundation of China(Grant No.61121064)
文摘A kind of photonic crystal structure with modulation of the refractive index is investigated both experimentally and theoretically for exploiting electromagnetically induced transparency（EIT）.The combination of EIT with periodically modulated refractive index medium gives rise to high efficiency reflection as well as forbidden transmission in a threelevel atomic system coupled by standing wave.We show an accurate theoretical simulation via transfer-matrix theory,automatically accounting for multilayer reflections,thus fully demonstrate the existence of photonic crystal structure in atomic vapor.
基金Project supported by the Key Science and Technology Research Project of Henan Province,China(Grant Nos.162102210164 and 1721023100107)the Natural Science Foundation of Henan Educational Committee,China(Grant No.17A140002)
文摘A graphene-based metamaterial for THz plasmon induced transparency(PIT) is presented and numerically studied in this paper, which consists of two horizontal graphene strips attached to a continuous vertical wire separately. The calculated surface current distributions demonstrate that the distinct PIT window results from the near-field coupling of two bright modes. To explore the physical mechanism of PIT effect, we employ the coupled Lorentz oscillator model. The transmission spectra obtained with this model fits well with the simulation results. The performance of the PIT system can be controlled through the geometry parameters of graphene strips. Moreover, the transparency window can be dynamically tuned by varying the Fermi energy and the carrier mobility of the graphene strips. The slow light effect is also explored in our proposed structure and it can achieve 1.25 ps when Fermi energy is 1.3 eV. Finally, the position of the transmission window with the variation of the nearby medium refractive index is examined. Such a proposed graphene-based PIT system may have great potential applications in photonic devices.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.11174051,11004026,11074034,and 61271057)the National Basic Research Program of China (Grant No.2010CB923401)the Youth Study Plan from Southeast University
文摘Electromagnetically induced transparency （EIT） is obtained in a symmetric U-shaped metamaterial, which is at- tributed to the simultaneously excited dual modes in a single resonator under lateral incidence. A large group index accom- panied with a sharp EIT-like transparency window offers potential applications for slowing down light and sensing.
基金Project supported by the National Natural Science Foundation of China(Grant No.11304010)
文摘We study the optical properties of a two-level atomic ensemble controlled by a high-finesse cavity. Even though the cavity is initially in the vacuum state in the absence of external driving, the probe response of the atomic ensemble can be dramatically modified. When the collectively enhanced atom–cavity coupling is strong enough and the cavity decay rate is much smaller than the atomic damping rate, an electromagnetically induced transparency-like coherent phenomenon emerges with a dip absorption for the response of the two-level atoms in the cavity without driving, and thus is called vacuum induced transparency. We also show the slow light with very low group velocity in such an atomic ensemble.
基金Project supported by the National Key Basic Research Program of China(Grant No.2013CB922003)the National Natural Science Foundation of China(Grant Nos.91421305,91121005,and 11174329)
文摘We have experimentally offset-locked the frequencies of two lasers using electromagnetically induced transparency（EIT） spectroscopy of ^（85）Rb vapor with a buffer gas in a magnetic field at room temperature. The magnetic field is generated by a permanent magnet mounted on a translation stage and its field magnitude can be varied by adjusting the distance between the magnet and Rb cell, which maps the laser locking frequency to the space position of the magnet. This frequency-space mapping technique provides an unambiguous daily laser frequency detuning operation with high accuracy.A repeatability of less than 0.5 MHz is achieved with the locking frequency detuned up to 184 MHz when the magnetic field varies from 0 up to 80 G.
基金Project supported by the National Key Basic Research Program of China(Grant No.2013CB922003)the National Natural Science Foundation of China(Grant Nos.91421305,91121005,11674359,and 91436106)
文摘We have studied the phenomenon of electromagnetically induced transparency（EIT） of ^87Rb vapor with a buffer gas in a magnetic field at room temperature. It is found that the spectral lines caused by the velocity selective optical pump effects get much weaker and wider when the sample cell is mixed with a 5-Torr N_2 gas while the EIT signal is kept almost unchanged. A weighted least-square fit is also developed to remove the Doppler broadening completely. This spectral method provides a way to measure the Zeeman splitting with high resolution, for example, the Λ-type EIT resonance splits into four peaks on the D_2 line of ^87Rb in the thermal 2-cm vapor cell with a magnetic field along the electric field of the linearly polarized coupling laser. The high-resolution spectrum can be used to lock the laser to a given frequency by tuning the magnetic field.
基金Project supported by the National Basic Research Program of China(Grant No.2012CB921603)the National Natural Science Foundation of China(Grants Nos.11274209,61475090,61378039,and 61378013)the Research Project Supported by Shanxi Scholarship Council of China(Grant No.2014-009)
文摘We present a laser frequency locking to Rydberg transition with electromagnetically induced transparency（EIT）spectra in a room-temperature cesium vapor cell. Cesium levels 6S_（1/2）, 6P_（3/2）, and the n D_（5/2） state, compose a cascade three-level system, where a coupling laser drives Rydberg transition, and probe laser detects the EIT signal. The error signal, obtained by demodulating the EIT signal, is used to lock the coupling laser frequency to Rydberg transition. The laser frequency fluctuation, ~0.7 MHz, is obtained after locking on, with the minimum Allan variance to be 8.9 × 10^（-11）.This kind of locking method can be used to stabilize the laser frequency to the excited transition.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11404330,11274376,61308011,and 11474347)the NSAF,China(Grant No.U1330117)+1 种基金the National Basic Research Program of China(Grant Nos.2013CB922002 and 2010CB922904)the China Postdoctoral Science Foundation(Grant No.119103S239)
文摘We study the relationship between electromagnetically-induced transparency（EIT） and Autler–Townes（AT） splitting in a cascade three-level Doppler-broadened system. By comparing the absorption spectrum with the fluorescence excitation spectrum, it is found that for a Doppler-broadened system, EIT resonance cannot be explained as the result of quantum interference, unlike the case of a homogeneously broadened system. Instead, the macroscopic polarization interference plays an important role in determining the spectra of EIT and AT splitting, which can be explained within the same framework when being detected by the absorption spectra.
基金supported by the National Natural Science Foundation of China(Grant No.61378094)
文摘We study a three-mode double-cavity optomechanical system in which an oscillating membrane of perfect reflection is inserted between two fixed mirrors of partial transmission. We find that electromagnetically induced transparency （EIT） can be realized and controlled in this optomechanical system by adjusting the relative intensity and the relative phase between left-hand and right-hand input （probe and coupling） fields. In particular, one perfect EIT window is seen to occur when the two probe fields are exactly out of phase and the EIT window＇s width is very sensitive to the relative intensity of two coupling fields. Our numerical findings may be extended to achieve optomechanical storage and switching schemes applicable in quantum information processing.
基金Project supported by National Natural Science Foundation of China (Grant Nos. 10674060,10874043 and 10974181)by the National Basic Research Program of China (Grant Nos. 2005CB724508 and 2006CB921104)
文摘We study the ultraslow optical solitons in a resonant three-level atomic system via electromagnetically induced transparency under a density-matrix （DM） approach. The results of linear and nonlinear optical properties are compared with those obtained by using an amplitude variable （AV） approach. It is found that the results for both approaches are the same in the linear regime if the corresponding relations between the population-coherence decay rates in the DM approach and the energy-level decay rates in the AV approach are appropriately imposed. However, in the nonlinear regime there is a small difference for the self-phase modulation coefficient of the nonlinear SchrSdinger equation that governs the time evolution of probe pulse envelope. All analytical predicts are checked by numerical simulations.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61771434,91123036,61178058,61275166,and 61076111)the National Science Fund for Distinguished Young Scholars,China(Grant No.51225504)
文摘The coupled resonator-induced transparency （CRIT） phenomenon, which is analogous to electromagnetically induced transparency in atomic systems, can occur in an original integrated optical resonator system due to the coherent interference of the coupled optical resonators. The system was composed of three ring resonators on silicon, each with the same cavity size, and the optical coupling to the input and output ports was achieved using grating with a power coupling efficiency of 36%. A CRIT resonance whose spectrum shows a narrow transparency peak with a low group velocity was demonstrated. The quality factor of the ring resonator can attain a value up to 6x 104, and the harmonic wavelength can be controlled by adjusting the temperature. The through and drop transmission spectra of the resonator are reconciled well with each other and also consistent well with the theoretical analysis.
基金supported by the Doctoral Scientific Research Foundation of Henan Normal University(Grant No.20210397)the Henan Province Key Scientific Research Project Plan of Colleges and Universities(Grant No.23A140001)+1 种基金the National Natural Science Foundation of China(Grant Nos.11704103,12074106,61835013,and 12074105)the National Key R&D Program of China(Grant Nos.2021YFA1400900,2021YFA0718300,and 2021YFA1400243)。
文摘We theoretically study optomechanically induced transparency in a spinning Kerr-nonlinear resonator.The interplay between the optical Kerr effect and the Sagnac effect provides a flexible tool for modifying the optomechanically induced transparency windows of the signal comparing to the system of a single spinning resonator.It is found that the system will exhibit distinct transparency phenomenon and fast-to-slow light effects.More importantly,a symmetric transparency window appears by adjusting the rotation-induced Sagnac frequency shift to compensate for the Kerr-induced frequency shift.These results open up a new way to explore novel light propagation of optomechanically induced transparency devices in spinning resonators with Kerr nonlinearity.
基金supported by the National Basic Research Program of China under Grant No.2014CB339800
文摘A terahertz metamaterial sensor adopting the metamaterial-based electromagnetically induced transparency（EIT） effect is presented for determining the 1,4-dioxane concentration in its aqueous solution. The metamaterial sensor, which consists of an EIT element unit with a cut-wire metallic resonator and two split-ring metallic resonators fabricated on a 490-μm thick silicon substrate, operates in a transmission geometry. The EIT peak was red-shifted and decreased with the increase of the water volume. A maximum redshift about 54 GHz of the EIT peak was detected between the 1,4-dioxane and water. The presented linear behavior and high sensitivity of the EIT peak depending on the water concentration pave a novel avenue for sensor applications.
