Superbunching pseudothermal light has important applications in studying the second-and higher-order interference of light in quantum optics.Unlike the photon statistics of thermal or pseudothermal light is well under...Superbunching pseudothermal light has important applications in studying the second-and higher-order interference of light in quantum optics.Unlike the photon statistics of thermal or pseudothermal light is well understood,the photon statistics of superbunching pseudothermal light has not been studied yet.In this paper,we will employ single-photon detectors to measure the photon statistics of superbunching pseudothermal light and calculate the degree of second-order coherence.It is found that the larger the value of the degree of second-order coherence of superbunching pseudothermal light is,the more the measured photon distribution deviates from the one of thermal or pseudothermal light in the tail part.The results are helpful to understand the physics of two-photon superbunching with classical light.It is suggested that superbunching pseudothermal light can be employed to generate non-Rayleigh temporal speckles.展开更多
The oxygen adsorption can drastically alter the electronic properties of the two-dimensional(2D)materials,which is usually dificult to be removed.In this work,we report the ultraviolet(UV)ilumination induced desorptio...The oxygen adsorption can drastically alter the electronic properties of the two-dimensional(2D)materials,which is usually dificult to be removed.In this work,we report the ultraviolet(UV)ilumination induced desorption of the O2 molecules from the monolayer MoS2 surface by using the atmosphere dependent transport measurement,Kelvin probe microscopy,photoluminescence spectroscopy and X-ray photoelectron spectroscopy.Obvious increasing of the conductivity,rising of the Fermi level,and red shift of the photoluminescence peaks of the MoS2 were observed after the UV ilumination in vacuum,indicating the elimination of the depletion effect from the oxygen adsorption.Such parameter changes can be reversibly recovered by the subsequent O2 exposure.Furthermore,obvious decreasing of the oxygen concentration after the UV ilumination was also observed by X-ray photoelectron spectroscopy.Thus the UV induced O2 photodesorption effect is evidenced.The photo-excited charge transfer mechanism is proposed to account for the photodesorption effect.These results provide a nondestructive way to clean the MoS2 surface and manipulate the performance of the MoS2 based devices.展开更多
基金supported by the Shanxi Key Research and Development Project,China(Grant No.2019ZDLGY09-08)Shanxi Nature and Science Basic Research Project,China(Grant No.2019JLP-18)Open fund of MOE Key Laboratory of Weak-Light Nonlinear Photonics(Grant No.OS19-2)。
文摘Superbunching pseudothermal light has important applications in studying the second-and higher-order interference of light in quantum optics.Unlike the photon statistics of thermal or pseudothermal light is well understood,the photon statistics of superbunching pseudothermal light has not been studied yet.In this paper,we will employ single-photon detectors to measure the photon statistics of superbunching pseudothermal light and calculate the degree of second-order coherence.It is found that the larger the value of the degree of second-order coherence of superbunching pseudothermal light is,the more the measured photon distribution deviates from the one of thermal or pseudothermal light in the tail part.The results are helpful to understand the physics of two-photon superbunching with classical light.It is suggested that superbunching pseudothermal light can be employed to generate non-Rayleigh temporal speckles.
基金This work is supported by the National Natural Science Foundation of China(Nos.11074142 and 11021464)Collaborative Innovation Center of Weak Signal-Detecting Materials and Devices Integration of Anhui University(No.01001795-201601)+1 种基金Fundam ental Research Funds for the Central Universities(No.FRP-TP-18-076A1)the China Postdoctoral Science Foundation(No.2017M610857).
文摘The oxygen adsorption can drastically alter the electronic properties of the two-dimensional(2D)materials,which is usually dificult to be removed.In this work,we report the ultraviolet(UV)ilumination induced desorption of the O2 molecules from the monolayer MoS2 surface by using the atmosphere dependent transport measurement,Kelvin probe microscopy,photoluminescence spectroscopy and X-ray photoelectron spectroscopy.Obvious increasing of the conductivity,rising of the Fermi level,and red shift of the photoluminescence peaks of the MoS2 were observed after the UV ilumination in vacuum,indicating the elimination of the depletion effect from the oxygen adsorption.Such parameter changes can be reversibly recovered by the subsequent O2 exposure.Furthermore,obvious decreasing of the oxygen concentration after the UV ilumination was also observed by X-ray photoelectron spectroscopy.Thus the UV induced O2 photodesorption effect is evidenced.The photo-excited charge transfer mechanism is proposed to account for the photodesorption effect.These results provide a nondestructive way to clean the MoS2 surface and manipulate the performance of the MoS2 based devices.