Based on color-locking noisy field correlation in three Markovian stochastic models, phase dispersions of the Raman- and Rayleigh-enhanced four-wave mixing （FWM） have been investigated. The phase dispersions are mod...Based on color-locking noisy field correlation in three Markovian stochastic models, phase dispersions of the Raman- and Rayleigh-enhanced four-wave mixing （FWM） have been investigated. The phase dispersions are modified by both linewidth and time delay for negative time delay, but only by linewidth for positive time delay. Moreover, the results under narrowband condition are close to the nonmodified nonlinear dispersion and absorption of the material. Homodyne and heterodyne detections of the Raman, the Rayleigh and the mixing femtosecond difference-frequency polarization beats have also been investigated, separately.展开更多
We study the competition between dispersion and absorption of doubly-dressed four-wave mixing （DDFWM） and dressed six-wave mixing. In the case of weak coupling fields limit, we find DDFWM signal is affected by destr...We study the competition between dispersion and absorption of doubly-dressed four-wave mixing （DDFWM） and dressed six-wave mixing. In the case of weak coupling fields limit, we find DDFWM signal is affected by destructive interference between four-wave mixing（FWM） and six-wave mixing as wen as constructive interference between FWM and eight-wave mixing. By analysing the difference between two kinds of doubly dressing mechanisms （parallel cascade and nested cascade） in this opening five-level system, we can further understand the generated high-order nonlinear optical signal dressed by multi-fields.展开更多
Dressed four-wave mixing （DFWM） spectroscopy is investigated theoretically in some micrometric thin cells. It is found that DFWM spectra can be modified by polarization interference of atoms and transient effects in...Dressed four-wave mixing （DFWM） spectroscopy is investigated theoretically in some micrometric thin cells. It is found that DFWM spectra can be modified by polarization interference of atoms and transient effects induced by atom-wall collision. This modification can lead to width-narrowing of DFWM lines and facilitates to implement experiment of high resolution DFWM spectroscopy in a confined atomic system.展开更多
The transient transport of photo-generated carriers and temporal variation of the built-in field, during triggering in semi-insulating GaAs photoconductive switches, have been investigated by using a special Monte Car...The transient transport of photo-generated carriers and temporal variation of the built-in field, during triggering in semi-insulating GaAs photoconductive switches, have been investigated by using a special Monte Carlo particle simulator. It shows that the built-in field can exceed the intrinsic avalanche field of semi-insulating GaAs under certain optical and electrical conditions. In such a case, local breakdown ionization is considered to be responsible for the transition in GaAs high-gain switching. The optical and electrical triggering thresholds are calculated and the calculated values of optical and electrical thresholds and partial delay time are in agreement with the published experimental data.展开更多
Four-wavelength lasers from near-infrared to deep-ultraviolet range,532,830,415 and 208 nm,have been developed in one all-solid-state laser system.The laser system is pumped by a diode-Q-YLF laser at 532 nm,a Ti:sapph...Four-wavelength lasers from near-infrared to deep-ultraviolet range,532,830,415 and 208 nm,have been developed in one all-solid-state laser system.The laser system is pumped by a diode-Q-YLF laser at 532 nm,a Ti:sapphire laser and the nonlinear second-harmonic-generation crystals LBO and BBO are used to generate different wavelengths.Maximum average powers(repetition rate 1 kHz)of 1.1 W at 830 nm,380 mW at 415 nm,and 39 mW at 208 nm are obtained when the pumping power is 3.6 W.The main characteristics of this system are presented.展开更多
This paper studies the near transform-limited high-resolution tunable far-ultraviolet light which is generated by narrow-band tunable light both theoretically and experimentally.It shows the theoretical work about con...This paper studies the near transform-limited high-resolution tunable far-ultraviolet light which is generated by narrow-band tunable light both theoretically and experimentally.It shows the theoretical work about conversion efficiency of sum-frequency,which is restricted by phase-matching angle,walk-off angle and phase distortion and so on,and sets experiment to check this work successfully.Also the origin of chirp of dye laser is analysed.展开更多
We consider a five-level atomic folding system, which involve two kinds of dressing mechanisms （the nested- cascade and the sequential-cascade） in interaction of three-dressing fields, the numerical results show tha...We consider a five-level atomic folding system, which involve two kinds of dressing mechanisms （the nested- cascade and the sequential-cascade） in interaction of three-dressing fields, the numerical results show that three- dressing fields are interchangeable under certain conditions, which can be considered as two four-level sub-system configurations （a nested-cascade N configuration and a sequential-cascade inverted-Y configuration）.展开更多
Based on the polarization interference of Raman- and Rayleigh-enhanced four-wave mixing processes, heterodyne detection of the Raman, Rayleigh and coexisting Raman and Rayleigh femtosecond difference-frequency polariz...Based on the polarization interference of Raman- and Rayleigh-enhanced four-wave mixing processes, heterodyne detection of the Raman, Rayleigh and coexisting Raman and Rayleigh femtosecond difference-frequency polarization beats is investigated in the cw and the three Markovian stochastic models, respectively. These two processes exhibit asymmetric and symmetric spectra, respectively, and the thermal effect in them can be suppressed by field-correlation method. Such studies of coexisting Raman- and Rayleigh-enhanced four-wave mixing processes can have important applications in coherence quantum control, and quantum information processing.展开更多
A thin oriented bacteriorhodopsin(bR)film is deposited on a stainless steel slide by use of the electrophoretic sedimentation method.A junction is made with electrolyte gels having a counterelectrode to construct a bR...A thin oriented bacteriorhodopsin(bR)film is deposited on a stainless steel slide by use of the electrophoretic sedimentation method.A junction is made with electrolyte gels having a counterelectrode to construct a bR-based photoelectric detector.The photoelectric response signal to a 10ns laser pulse is measured.A theory on the photoelectric kinetics of bR is developed based on the concept of the charge displacement current and the bR photocycle rate equations.Comparison between the theoretical and experimental results proves that the bR photoelectric response to a short laser pulse is a multi-exponential process.The decay time constants and amplitudes of each exponential component are obtained by data fitting.展开更多
This paper investigates the absorptive reduction and the width narrowing of electromagnetically induced transparency （EIT） in a thin vapour film of A-type atoms confined between two dielectric walls whose thickness ...This paper investigates the absorptive reduction and the width narrowing of electromagnetically induced transparency （EIT） in a thin vapour film of A-type atoms confined between two dielectric walls whose thickness is comparable with the wavelength of the probe field. The absorptive lines of the weak probe field exhibit strong reductions and very narrow EIT dips, which mainly results from the velocity slow-down effects and transient behaviour of atoms in a confined system. It is also shown that the lines are modified by the strength of the coupling field and the ratio of L/λ, with L the film thickness and λthe wavelength of the probe field. A simple robust recipe for EIT in a thin medium is achievable in experiment.展开更多
The near-threshold highly bound states of all three stable isotopic variants of molecular hydrogen have been studied. Numerous perturbations and unexpected transitions are observed as far as 1cm^-1 just below the seco...The near-threshold highly bound states of all three stable isotopic variants of molecular hydrogen have been studied. Numerous perturbations and unexpected transitions are observed as far as 1cm^-1 just below the second dissociation threshold. This complex structure may arise from a combination of nonadiabatic coupling between B, B＇, C electronic states, perturbations due to fine and hyperfine interactions, and strong shape resonances. The perturbed near-threshold states and vibrational continuum exhibit finegralned structure, differing greatly between isotopes because of varying nonadiabatic coupling.展开更多
We study the colour-locked twin-noisy-field correlation effects in the fifth-order nonlinear susceptibility of ultrafast polarization beats in a cascade four-level system. More importantly, the fifth-order phase-sensi...We study the colour-locked twin-noisy-field correlation effects in the fifth-order nonlinear susceptibility of ultrafast polarization beats in a cascade four-level system. More importantly, the fifth-order phase-sensitive heterodyne detection of ultrafast polarization beats has been exploited. The fifth-order nonlinear optical response can be controlled and modified through the colour-locked correlation of twin noisy fields. Thus, this method with the phase dispersion information is a good way to measure the real and imaginary parts of the fifth-order nonlinear susceptibility.展开更多
This paper presents a theoretical study of wavelength dependence four-wave-mixing （FWM） spectroscopy in a micrometric thin atomic vapour. It compares three cases termed as mismatched case I, matched case and mismatc...This paper presents a theoretical study of wavelength dependence four-wave-mixing （FWM） spectroscopy in a micrometric thin atomic vapour. It compares three cases termed as mismatched case I, matched case and mismatched case II for the probe wavelength less, equal and greater than the pump wavelength respectively. It finds that Dicke- narrowing can overcome width broadening induced by Doppler effects and polarisation interference of thermal atoms, and high resolution FWM spectra can be achieved both in matched and mismatched wavelength for many cases. It also finds that the magnitude of the FWM signal can be dramatically modified to be suppressed or to be enhanced in comparison with that of matched wavelength in mismatched case I or II. The width narrowing and the magnitude suppression or enhancement can be demonstrated by considering enhanced contribution of slow atoms induced by atom-wall collision and transient effect of atom-light interaction in a micrometric thin vapour.展开更多
The dressed four- and six-wave mixings in a V-type four-level system are considered. Under two different dressed conditions, two- and three-photon resonant Autler-Townes splittings, accompanied by enhancement and supp...The dressed four- and six-wave mixings in a V-type four-level system are considered. Under two different dressed conditions, two- and three-photon resonant Autler-Townes splittings, accompanied by enhancement and suppression of wave mixing signal, are obtained analytically. Meanwhile, an electromagnetic induced transparency of multi-wave mixing is presented, which shows multiple peaks and asymmetric effects caused by one-photon, two-photon and three-photon resonances, separately. The slow light propagation multiple region of multi-wave mixing signal is also obtained.展开更多
We have investigated the dressed effects of non-degenerate four-wave mixing （NDFWM） and demonstrated a phase-sensitive method of studying the fifth-order nonlinear susceptibility due to atomic coherence in RN-type f...We have investigated the dressed effects of non-degenerate four-wave mixing （NDFWM） and demonstrated a phase-sensitive method of studying the fifth-order nonlinear susceptibility due to atomic coherence in RN-type four-level system. In the presence of a strong coupling field, NDFWM spectrum exhibits Autler-Townes splitting, accompanied by either suppression or enhancement of the NDFWM signal, which is directly related to the competition between the absorption and dispersion contributions. The heterodyne-deteeted nonlinear absorption and dispersion of six-wave mixing signal in the RN-type system show that the hybrid radiation-matter detuning damping oscillation is in the THz range and can be controlled and modified through the eolour-locked correlation of twin noisy fields.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 60678005)the Foundation for the Authorof National Excellent Doctoral Dissertation of China (Grant No 200339)+1 种基金the For Ying-Tong Education Foundation for Young Teachers in the Institutions of Higher Education of China (Grant No 101061)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No 20050398017)
文摘Based on color-locking noisy field correlation in three Markovian stochastic models, phase dispersions of the Raman- and Rayleigh-enhanced four-wave mixing （FWM） have been investigated. The phase dispersions are modified by both linewidth and time delay for negative time delay, but only by linewidth for positive time delay. Moreover, the results under narrowband condition are close to the nonmodified nonlinear dispersion and absorption of the material. Homodyne and heterodyne detections of the Raman, the Rayleigh and the mixing femtosecond difference-frequency polarization beats have also been investigated, separately.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60308002 and 60678005, the Foundation for the National Excellent Doctoral Dissertation of China under Grant No 200339, the Foundation for the Key Programme of Ministry of Education of China under Grant No 105156, the For Ying-Tong Education Foundation for Young Teachers in the Institution of Higher Education of China under Grant No 101061, and the Specialized Research Fund for the Doctoral Programme of Higher Education of China under Gant No 20050698017.
文摘We study the competition between dispersion and absorption of doubly-dressed four-wave mixing （DDFWM） and dressed six-wave mixing. In the case of weak coupling fields limit, we find DDFWM signal is affected by destructive interference between four-wave mixing（FWM） and six-wave mixing as wen as constructive interference between FWM and eight-wave mixing. By analysing the difference between two kinds of doubly dressing mechanisms （parallel cascade and nested cascade） in this opening five-level system, we can further understand the generated high-order nonlinear optical signal dressed by multi-fields.
基金Support from the National Natural Science Foundation of China under Grant No 10874139, and the Major Program of Science Foundation of Xi＇an University of Arts and Science.
文摘Dressed four-wave mixing （DFWM） spectroscopy is investigated theoretically in some micrometric thin cells. It is found that DFWM spectra can be modified by polarization interference of atoms and transient effects induced by atom-wall collision. This modification can lead to width-narrowing of DFWM lines and facilitates to implement experiment of high resolution DFWM spectroscopy in a confined atomic system.
基金Supported by the National Natural Science Foundation of China under Grant No.50077017.
文摘The transient transport of photo-generated carriers and temporal variation of the built-in field, during triggering in semi-insulating GaAs photoconductive switches, have been investigated by using a special Monte Carlo particle simulator. It shows that the built-in field can exceed the intrinsic avalanche field of semi-insulating GaAs under certain optical and electrical conditions. In such a case, local breakdown ionization is considered to be responsible for the transition in GaAs high-gain switching. The optical and electrical triggering thresholds are calculated and the calculated values of optical and electrical thresholds and partial delay time are in agreement with the published experimental data.
基金Supported by the National Natural Science Foundation of China under Grant No.69778012the State Climbing Program under Grant No.59707042.
文摘Four-wavelength lasers from near-infrared to deep-ultraviolet range,532,830,415 and 208 nm,have been developed in one all-solid-state laser system.The laser system is pumped by a diode-Q-YLF laser at 532 nm,a Ti:sapphire laser and the nonlinear second-harmonic-generation crystals LBO and BBO are used to generate different wavelengths.Maximum average powers(repetition rate 1 kHz)of 1.1 W at 830 nm,380 mW at 415 nm,and 39 mW at 208 nm are obtained when the pumping power is 3.6 W.The main characteristics of this system are presented.
基金Project supported by the National Natural Science Foundation of China (Grant No 60678005)the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No 200339)+1 种基金the For Ying-Tong Education for Young Teachers in the Institutions of Higher Education of China (Grant No 101061)the Specialized Research Found for the Doctoral Program of Higher Education of China (Grant No 20050398017)
文摘This paper studies the near transform-limited high-resolution tunable far-ultraviolet light which is generated by narrow-band tunable light both theoretically and experimentally.It shows the theoretical work about conversion efficiency of sum-frequency,which is restricted by phase-matching angle,walk-off angle and phase distortion and so on,and sets experiment to check this work successfully.Also the origin of chirp of dye laser is analysed.
基金Supported by the National Natural Science Foundation of China under Grant No 60678005, the Foundation for the Author of National Excellent Doctoral Dissertation of China under Grant No 200339, the For Ying-Tong Education for Young Teachers in the Institutions of Higher Education of China under Grant No 101061, and the Specialized Research Found for the Doctoral Programme of Higher Education of China under Grant No 20050398017.
文摘We consider a five-level atomic folding system, which involve two kinds of dressing mechanisms （the nested- cascade and the sequential-cascade） in interaction of three-dressing fields, the numerical results show that three- dressing fields are interchangeable under certain conditions, which can be considered as two four-level sub-system configurations （a nested-cascade N configuration and a sequential-cascade inverted-Y configuration）.
基金Supported by the National Natural Science Foundation of China under Grant No 60678005, the Foundation for the Author of National Excellent Doctoral Dissertation of China under Grant No 200339, the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No 20050698017, the For Ying-Tong Education Foundation for Young Teachers in the Institutions of Higher Education of China under Grant No 101061, the New Century Excellent Talent Project of the Ministry of Education of China under Grant No NCET-08-0431.
文摘Based on the polarization interference of Raman- and Rayleigh-enhanced four-wave mixing processes, heterodyne detection of the Raman, Rayleigh and coexisting Raman and Rayleigh femtosecond difference-frequency polarization beats is investigated in the cw and the three Markovian stochastic models, respectively. These two processes exhibit asymmetric and symmetric spectra, respectively, and the thermal effect in them can be suppressed by field-correlation method. Such studies of coexisting Raman- and Rayleigh-enhanced four-wave mixing processes can have important applications in coherence quantum control, and quantum information processing.
基金Supported by the Foundation of State Key Laboratory of Transient Optics and Technology under Grant No.YAK9705the President Foundation of Chinese Academy of Sciences under Grant No.40007059.
文摘A thin oriented bacteriorhodopsin(bR)film is deposited on a stainless steel slide by use of the electrophoretic sedimentation method.A junction is made with electrolyte gels having a counterelectrode to construct a bR-based photoelectric detector.The photoelectric response signal to a 10ns laser pulse is measured.A theory on the photoelectric kinetics of bR is developed based on the concept of the charge displacement current and the bR photocycle rate equations.Comparison between the theoretical and experimental results proves that the bR photoelectric response to a short laser pulse is a multi-exponential process.The decay time constants and amplitudes of each exponential component are obtained by data fitting.
文摘This paper investigates the absorptive reduction and the width narrowing of electromagnetically induced transparency （EIT） in a thin vapour film of A-type atoms confined between two dielectric walls whose thickness is comparable with the wavelength of the probe field. The absorptive lines of the weak probe field exhibit strong reductions and very narrow EIT dips, which mainly results from the velocity slow-down effects and transient behaviour of atoms in a confined system. It is also shown that the lines are modified by the strength of the coupling field and the ratio of L/λ, with L the film thickness and λthe wavelength of the probe field. A simple robust recipe for EIT in a thin medium is achievable in experiment.
文摘The near-threshold highly bound states of all three stable isotopic variants of molecular hydrogen have been studied. Numerous perturbations and unexpected transitions are observed as far as 1cm^-1 just below the second dissociation threshold. This complex structure may arise from a combination of nonadiabatic coupling between B, B＇, C electronic states, perturbations due to fine and hyperfine interactions, and strong shape resonances. The perturbed near-threshold states and vibrational continuum exhibit finegralned structure, differing greatly between isotopes because of varying nonadiabatic coupling.
基金Project supported by the National Natural Science Foundation of China(Grant Nos60308002and60678005)the Foundation for the Author of National Excellent Doctoral Dissertation of China(Grant No200339)+2 种基金the Foundation for Key Program of Ministry of Education,China(Grant No105156)the Fok Ying-Tong Education Foundation for Young Teachers in the Higher Education Institutions of China(Grant No101061)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No20050698017)
文摘We study the colour-locked twin-noisy-field correlation effects in the fifth-order nonlinear susceptibility of ultrafast polarization beats in a cascade four-level system. More importantly, the fifth-order phase-sensitive heterodyne detection of ultrafast polarization beats has been exploited. The fifth-order nonlinear optical response can be controlled and modified through the colour-locked correlation of twin noisy fields. Thus, this method with the phase dispersion information is a good way to measure the real and imaginary parts of the fifth-order nonlinear susceptibility.
基金supported from the Major Program of Science Foundation of Xi’an University of Arts and Science
文摘This paper presents a theoretical study of wavelength dependence four-wave-mixing （FWM） spectroscopy in a micrometric thin atomic vapour. It compares three cases termed as mismatched case I, matched case and mismatched case II for the probe wavelength less, equal and greater than the pump wavelength respectively. It finds that Dicke- narrowing can overcome width broadening induced by Doppler effects and polarisation interference of thermal atoms, and high resolution FWM spectra can be achieved both in matched and mismatched wavelength for many cases. It also finds that the magnitude of the FWM signal can be dramatically modified to be suppressed or to be enhanced in comparison with that of matched wavelength in mismatched case I or II. The width narrowing and the magnitude suppression or enhancement can be demonstrated by considering enhanced contribution of slow atoms induced by atom-wall collision and transient effect of atom-light interaction in a micrometric thin vapour.
基金Project supported by the National Natural Science Foundation of China （Grant Nos 60308002 and 60678005）, the Foundation for the Author of National Excellent Doctoral Dissertation of China （Grant No 200339）, the Foundation for Key Program of Ministry of Education,China （Grant No 105156）, the For Ying-Tong Education Foundation for Young Teachers in the Institutions of Higher Education of China （Grant No 101061） and the Specialized Research Pund for the Doctoral Program of Higher Education of China （Grant No 20050698017）.
文摘The dressed four- and six-wave mixings in a V-type four-level system are considered. Under two different dressed conditions, two- and three-photon resonant Autler-Townes splittings, accompanied by enhancement and suppression of wave mixing signal, are obtained analytically. Meanwhile, an electromagnetic induced transparency of multi-wave mixing is presented, which shows multiple peaks and asymmetric effects caused by one-photon, two-photon and three-photon resonances, separately. The slow light propagation multiple region of multi-wave mixing signal is also obtained.
基金Project supported by the National Natural Science Foundation of China （Grant Nos 60308002 and 60678005）, the Foundation for the Author of National Excellent Doctoral Dissertation of China （Grant No 200339）, the Research Foundation from Ministry of Education of China （Grant No 105156）, the For Ying-Tong Education Foundation for Young Teachers of Higher Education Institutions of China （Grant No 101061） and the Specialized Research Fund for the Doctoral Program of Higher Education of China （Grant No 20050698017）.
文摘We have investigated the dressed effects of non-degenerate four-wave mixing （NDFWM） and demonstrated a phase-sensitive method of studying the fifth-order nonlinear susceptibility due to atomic coherence in RN-type four-level system. In the presence of a strong coupling field, NDFWM spectrum exhibits Autler-Townes splitting, accompanied by either suppression or enhancement of the NDFWM signal, which is directly related to the competition between the absorption and dispersion contributions. The heterodyne-deteeted nonlinear absorption and dispersion of six-wave mixing signal in the RN-type system show that the hybrid radiation-matter detuning damping oscillation is in the THz range and can be controlled and modified through the eolour-locked correlation of twin noisy fields.
