Topological slow light and rainbow trapping tend to rely on large-scale interface structure in previous research work,which have restricted further miniaturization.In this work,we propose a method to realize slow ligh...Topological slow light and rainbow trapping tend to rely on large-scale interface structure in previous research work,which have restricted further miniaturization.In this work,we propose a method to realize slow light and rainbow trapping at the zigzag edge of a single valley photonic crystals(VPCs)bounded by air,which is very different from previous studies where rainbow trapping is supported at the interface separating two VPCs with inversion symmetry.By constructing the VPC–air boundaries and VPC–VPC interfaces experimentally,we have observed the topologically protected rainbow trapping simultaneously at the external and internal boundary.This work provides a feasible platform for the miniaturized optical communication devices such as optical buffers,optical storage and optical routing.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
We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion ...We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion symmetry. We investigate how the shot noise properties vary as the relative amplitude between the two parity components in the pairing potential is changed. It is demonstrated that some characteristics of the electrical shot noise properties of such tunnel junctions may depend sensitively on the relative amplitude between the two parity components in the pairing potential, and some significant changes may occur in the electrical shot noise properties when the relative amplitude between the two parity components is varied from the singlet s-wave pairing dominated regime to the chiral triplet p-wave pairing dominated regime. In the chiral triplet p-wave pairing dominated regime, the ratio of noise power to electric current is close to 2e both in the in-gap and in the out-gap region. In the singlet s-wave pairing dominated regime, the value of this ratio is close to 4e in the inner gap region but may reduce to about 2e in the outer gap region as the relative amplitude of the chiral triplet pairing component is increased. The variations of the differential shot noise with the bias voltage also exhibit some significantly different features in different regimes. Such different features can serve as useful diagnostic tools for the determination of the relative magnitude of the two parity components in the pairing potential.展开更多
Compared with the transverse isotropic(TI)medium,the orthorhombic anisotropic medium has both horizontal and vertical symmetry axes and it can be approximated as a set of vertical fissures developed in a group of hori...Compared with the transverse isotropic(TI)medium,the orthorhombic anisotropic medium has both horizontal and vertical symmetry axes and it can be approximated as a set of vertical fissures developed in a group of horizontal strata.Although the full-elastic orthorhombic anisotropic wave equation can accurately simulate seismic wave propagation in the underground media,a huge computational cost is required in seismic modeling,migration,and inversion.The conventional coupled pseudo-acoustic wave equations based on acoustic approximation can be used to significantly reduce the cost of calculation.However,these equations usually suffer from unwanted shear wave artifacts during wave propagation,and the presence of these artifacts can significantly degrade the imaging quality.To solve these problems,we derived a new pure P-wave equation for orthorhombic media that eliminates shear wave artifacts while compromising computational efficiency and accuracy.In addition,the derived equation involves pseudo-differential operators and it must be solved by 3D FFT algorithms.In order to reduce the number of 3D FFT,we utilized the finite difference and pseudo-spectral methods to conduct 3D forward modeling.Furthermore,we simplified the equation by using elliptic approximation and implemented 3D reverse-time migration(RTM).Forward modeling tests on several homogeneous and heterogeneous models confirm that the accuracy of the new equation is better than that of conventional methods.3D RTM imaging tests on three-layer and SEG/EAGE 3D salt models confirm that the ORT media have better imaging quality.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12374302)the Natural Science Foundation of Chongqing(Grant No.CSTB2022NSCQMSX0872).
文摘Topological slow light and rainbow trapping tend to rely on large-scale interface structure in previous research work,which have restricted further miniaturization.In this work,we propose a method to realize slow light and rainbow trapping at the zigzag edge of a single valley photonic crystals(VPCs)bounded by air,which is very different from previous studies where rainbow trapping is supported at the interface separating two VPCs with inversion symmetry.By constructing the VPC–air boundaries and VPC–VPC interfaces experimentally,we have observed the topologically protected rainbow trapping simultaneously at the external and internal boundary.This work provides a feasible platform for the miniaturized optical communication devices such as optical buffers,optical storage and optical routing.
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.
文摘We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion symmetry. We investigate how the shot noise properties vary as the relative amplitude between the two parity components in the pairing potential is changed. It is demonstrated that some characteristics of the electrical shot noise properties of such tunnel junctions may depend sensitively on the relative amplitude between the two parity components in the pairing potential, and some significant changes may occur in the electrical shot noise properties when the relative amplitude between the two parity components is varied from the singlet s-wave pairing dominated regime to the chiral triplet p-wave pairing dominated regime. In the chiral triplet p-wave pairing dominated regime, the ratio of noise power to electric current is close to 2e both in the in-gap and in the out-gap region. In the singlet s-wave pairing dominated regime, the value of this ratio is close to 4e in the inner gap region but may reduce to about 2e in the outer gap region as the relative amplitude of the chiral triplet pairing component is increased. The variations of the differential shot noise with the bias voltage also exhibit some significantly different features in different regimes. Such different features can serve as useful diagnostic tools for the determination of the relative magnitude of the two parity components in the pairing potential.
基金supported by the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(No.2021QNLM020001)the Major Scientific and Technological Projects of Shandong Energy Group(No.SNKJ2022A06-R23)+2 种基金the Funds of Creative Research Groups of China(No.41821002)National Natural Science Foundation of China Outstanding Youth Science Fund Project(Overseas)(No.ZX20230152)the Major Scientific and Technological Projects of CNPC(No.ZD2019-183-003)。
文摘Compared with the transverse isotropic(TI)medium,the orthorhombic anisotropic medium has both horizontal and vertical symmetry axes and it can be approximated as a set of vertical fissures developed in a group of horizontal strata.Although the full-elastic orthorhombic anisotropic wave equation can accurately simulate seismic wave propagation in the underground media,a huge computational cost is required in seismic modeling,migration,and inversion.The conventional coupled pseudo-acoustic wave equations based on acoustic approximation can be used to significantly reduce the cost of calculation.However,these equations usually suffer from unwanted shear wave artifacts during wave propagation,and the presence of these artifacts can significantly degrade the imaging quality.To solve these problems,we derived a new pure P-wave equation for orthorhombic media that eliminates shear wave artifacts while compromising computational efficiency and accuracy.In addition,the derived equation involves pseudo-differential operators and it must be solved by 3D FFT algorithms.In order to reduce the number of 3D FFT,we utilized the finite difference and pseudo-spectral methods to conduct 3D forward modeling.Furthermore,we simplified the equation by using elliptic approximation and implemented 3D reverse-time migration(RTM).Forward modeling tests on several homogeneous and heterogeneous models confirm that the accuracy of the new equation is better than that of conventional methods.3D RTM imaging tests on three-layer and SEG/EAGE 3D salt models confirm that the ORT media have better imaging quality.
