In t.his contribution, we briefly recall the basic concepts of quantum optics and properties of semicon- ductor quantum clot. （QD） which a.re necessary to the nnderstanding of the physics of single-photon generation...In t.his contribution, we briefly recall the basic concepts of quantum optics and properties of semicon- ductor quantum clot. （QD） which a.re necessary to the nnderstanding of the physics of single-photon generation with single QDs. Firstly, we address the theory of quantmn emitter-cavity system, the fluorescence and optical properties of semiconductor QDs, and the photon statistics as well as opti- cal properties of the QDs. We then review the localizatioll of single semiconductor QDs in quantum confined optical microcavity systems to achieve their overall optical properties and perfornances in terms of strong coupling regime, elfieiency, directionality, and polarization control. Furthermore, we will discuss the recenl, progress on the fabrication of single photon sources, and various a.pproaehes for embedding single QDs into mieroca,vities or photonic crystal nanoeavities and show how to ex- tend the wavelength range. We focus in part;icular on new generations of electrically driven QD single photon source leading to high repetition rates, efficiencies at elevated temperature operation. Besides strong eoupling regime, and high collection new development;s of room temperature sin- gle photon emission in the strong coupling regime are reviewed. The generation of indistinguishable photons and remaining challenges for pract ical single-photon sources are also discussed.展开更多
We have investigated the optical properties of single CdSe/ZnS nanocrystals by conducting combinations of experiments on antibunching and photoluminescence intermittence under different experimental conditions.Based o...We have investigated the optical properties of single CdSe/ZnS nanocrystals by conducting combinations of experiments on antibunching and photoluminescence intermittence under different experimental conditions.Based on photoluminescence in an antibunching experiment,we analyzed the emission lifetime of QDs by using stretched exponentials.The difference between the parameters obtained from average lifetimes and stretched exponents were analyzed by considering the effect of nonradiative emission.An Auger-assisted tunneling model was used to explain the power law exponents of off time distribution.The power law exponent under high excitation power was correlated with a higher Auger ionization rate.Using the parameters obtained from stretched exponential function and power law,the antibunching phenomena at different time and under different excitation intensity were analyzed.展开更多
The 1.55-μm quantum-dot (QD) micropillar cavities are strongly required as single photon sources (SPSs) for silica-fiber-based quantum information processing. Theoretical analysis shows that the adiabatic distributed...The 1.55-μm quantum-dot (QD) micropillar cavities are strongly required as single photon sources (SPSs) for silica-fiber-based quantum information processing. Theoretical analysis shows that the adiabatic distributed Bragg reflector (DBR) structure may greatly improve the quality of a micropillar cavity. An InGaAsP/InP micropillar cavity is originally difficult, but it becomes more likely usable with inserted tapered (thickness decreased towards the center) distributed DBRs. Simulation turns out that, incorporating adiabatically tapered DBRs, a Si/SiO2- InP hybrid micropillar cavity, which enables weakly coupling InAs/InP quantum dots (QDs), can even well satisfy strong coupling at a smaller diameter. Certainly, not only the tapered structure, other adiabatic designs, e.g., both DBR layers getting thicker and one thicker one thinner, also improve the quality, reduce the diameter, and degrade the fabrication difficulty of Si/SiO2-InP hybrid micropillar cavities. Furthermore, the problem of the thin epitaxial semiconductor layer can also be greatly resolved by inserting adiabatic InGaAsP/InP DBRs. With tapered DBRs, the InGaAsP/InP-air-aperture micro-pillar cavity serves as an efficient, coherent, and monolithically producible 1.55-μm single-photon source (SPS). The adiabatic design is thus an effective way to obtain prospective candidates for 1.55-μm QD SPSs.展开更多
基金G. Shan would like to thank Prof. C. Cohen-Tannoudji （Nobel Laureate in 1997） for his fruitful discus- sion on quantum optics and particularly theory of quantum-dot- cavity during his visit at City University of Hong Kong in 2012. This work was partially sponsored by General Research Grant Project No. CityU 119212 from RGC, Hong Kong, and the re- search activity fund from CityU to support research work as a visiting scholar at Columbia University. W. Huang acknowledges the support from the National Basic Research Program of China （973 Program, Grant No. 2009CB930601）. Z. Yin acknowledges the support by the National Basic Research Program of China （973 Program, Grant Nos. 2011CBA00300 and 2011CBA00302）, and the National Natural Science Foundation of China （Grant Nos. 61033001 and 11105136）.
文摘In t.his contribution, we briefly recall the basic concepts of quantum optics and properties of semicon- ductor quantum clot. （QD） which a.re necessary to the nnderstanding of the physics of single-photon generation with single QDs. Firstly, we address the theory of quantmn emitter-cavity system, the fluorescence and optical properties of semiconductor QDs, and the photon statistics as well as opti- cal properties of the QDs. We then review the localizatioll of single semiconductor QDs in quantum confined optical microcavity systems to achieve their overall optical properties and perfornances in terms of strong coupling regime, elfieiency, directionality, and polarization control. Furthermore, we will discuss the recenl, progress on the fabrication of single photon sources, and various a.pproaehes for embedding single QDs into mieroca,vities or photonic crystal nanoeavities and show how to ex- tend the wavelength range. We focus in part;icular on new generations of electrically driven QD single photon source leading to high repetition rates, efficiencies at elevated temperature operation. Besides strong eoupling regime, and high collection new development;s of room temperature sin- gle photon emission in the strong coupling regime are reviewed. The generation of indistinguishable photons and remaining challenges for pract ical single-photon sources are also discussed.
基金supported by the National Natural Science Foundation of China (Grant No 60877030)National High Technology Research and Development Program of China (Grant No 2009AA03Z406)Grant-in-Aid for Scientific Research (C) (Grant No 20510112)
文摘We have investigated the optical properties of single CdSe/ZnS nanocrystals by conducting combinations of experiments on antibunching and photoluminescence intermittence under different experimental conditions.Based on photoluminescence in an antibunching experiment,we analyzed the emission lifetime of QDs by using stretched exponentials.The difference between the parameters obtained from average lifetimes and stretched exponents were analyzed by considering the effect of nonradiative emission.An Auger-assisted tunneling model was used to explain the power law exponents of off time distribution.The power law exponent under high excitation power was correlated with a higher Auger ionization rate.Using the parameters obtained from stretched exponential function and power law,the antibunching phenomena at different time and under different excitation intensity were analyzed.
基金the financial support from the National Natural Science Foundation of China(11774326)the National Key R&D Program of China(2017YFA0304301)+2 种基金Innovation Program for Quantum Science and Technology(2021ZD0300204)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)Anhui Initiative in Quantum Information Technologies。
基金supported by the Sichuan Science and Technology Program under Grant No.2018JY0084
文摘The 1.55-μm quantum-dot (QD) micropillar cavities are strongly required as single photon sources (SPSs) for silica-fiber-based quantum information processing. Theoretical analysis shows that the adiabatic distributed Bragg reflector (DBR) structure may greatly improve the quality of a micropillar cavity. An InGaAsP/InP micropillar cavity is originally difficult, but it becomes more likely usable with inserted tapered (thickness decreased towards the center) distributed DBRs. Simulation turns out that, incorporating adiabatically tapered DBRs, a Si/SiO2- InP hybrid micropillar cavity, which enables weakly coupling InAs/InP quantum dots (QDs), can even well satisfy strong coupling at a smaller diameter. Certainly, not only the tapered structure, other adiabatic designs, e.g., both DBR layers getting thicker and one thicker one thinner, also improve the quality, reduce the diameter, and degrade the fabrication difficulty of Si/SiO2-InP hybrid micropillar cavities. Furthermore, the problem of the thin epitaxial semiconductor layer can also be greatly resolved by inserting adiabatic InGaAsP/InP DBRs. With tapered DBRs, the InGaAsP/InP-air-aperture micro-pillar cavity serves as an efficient, coherent, and monolithically producible 1.55-μm single-photon source (SPS). The adiabatic design is thus an effective way to obtain prospective candidates for 1.55-μm QD SPSs.
