在对In As单量子点施加流体静压的实验中,使用了带有压电陶瓷的连续加压装置,在低温连续施加流体静压的情况下,可以调节量子点单激子能量兰移约320 me V。在对不同流体静压下单激子发光的二阶关联函数测量之后,证明流体静压并不影响单...在对In As单量子点施加流体静压的实验中,使用了带有压电陶瓷的连续加压装置,在低温连续施加流体静压的情况下,可以调节量子点单激子能量兰移约320 me V。在对不同流体静压下单激子发光的二阶关联函数测量之后,证明流体静压并不影响单激子发光的单光子特性。同时通过流体静压,可以实现量子点双激子态由反束缚态到束缚态的转变,并且给出了这一过程的偏振分辨光谱图。最后观察到单量子点精细结构劈裂随流体静压的增加而增加,而且精细结构劈裂的增加量可以达到约150μe V。展开更多
We report on the single photon emission from single InAs/GaAs self-assembled Stranski-Krastanow quantum dots up to 80 K under pulsed and continuous wave excitations. At temperature 8OK, the second-order correlation fu...We report on the single photon emission from single InAs/GaAs self-assembled Stranski-Krastanow quantum dots up to 80 K under pulsed and continuous wave excitations. At temperature 8OK, the second-order correlation function at zero time delay, g^（2）（0）, is measured to be 0.422 for pulsed excitation. At the same temperature under continuous wave excitation, the photon antibunching effect is observed. Thus, our experimental results demonstrate a promising potential application of self-assembled InAs/GaAs quantum dots in single photon emission at liquid nitrogen temperature.展开更多
Excitation power-dependent micro-photoluminescence spectra and photon-correlation measurement are used to study the optical properties and photon statistics of single InAs quantum dots. Exciton and biexciton emissions...Excitation power-dependent micro-photoluminescence spectra and photon-correlation measurement are used to study the optical properties and photon statistics of single InAs quantum dots. Exciton and biexciton emissions, whose photoluminescence intensities have linear and quadratic excitation power dependences, respectively, are identified. Under pulsed laser excitation, the zero time delay peak of second order correlation function corresponding to exciton emission is well suppressed, which is a clear evidence of single photon emission.展开更多
We report a photoluminescence （PL） energy red-shift of single quantum dots （QDs） by applying an in-plane compressive uniaxial stress along the [110] direction at a liquid nitrogen temperature. Uniaxial stress has ...We report a photoluminescence （PL） energy red-shift of single quantum dots （QDs） by applying an in-plane compressive uniaxial stress along the [110] direction at a liquid nitrogen temperature. Uniaxial stress has an effect not only on the confinement potential in the growth direction which results in the PL shift, but also on the cylindrical symmetry of QDs which can be reflected by the change of the full width at half maximum of PL peak. This implies that uniaxial stress has an important role in tuning PL energy and fine structure splitting of QDs.展开更多
We investigate the temperature dependence of photoluminescence from single and ensemble InAs/GaAs quantum dots systematically. As temperature increases, the exciton emission peak for single quantum dot shows broadenin...We investigate the temperature dependence of photoluminescence from single and ensemble InAs/GaAs quantum dots systematically. As temperature increases, the exciton emission peak for single quantum dot shows broadening and redshift. For ensemble quantum dots, however, the exciton emission peak shows narrowing and fast redshift. We use a simple steady-state rate equation model to simulate the experimental data of photoluminescence spectra. It is confirmed that carrier-phonon scattering gives the broadening of the exciton emission peak in single quantum dots while the effects of carrier thermal escape and retrapping play an important role in the narrowing and fast redshift of the exciton emission peak in ensemble quantum dots.展开更多
This paper studies the size dependence of biexciton binding energy in single quantum dots （QDs） by using atomic force microscopy and micro-photoluminescence measurements. It finds that the biexciton binding energies...This paper studies the size dependence of biexciton binding energy in single quantum dots （QDs） by using atomic force microscopy and micro-photoluminescence measurements. It finds that the biexciton binding energies in the QDs show ＂binding＂ and ＂antibinding＂ properties which correspond to the large and small sizes of QDs, respectively. The experimental results can be well interpreted by the biexciton potential curve, calculated from the exciton molecular model and the Heitler London method.展开更多
We report the coherent resonant emission of the exciton state in a single InAs quantum dot,embedded in a planar optical microcavity.The quantum dot is excited by a laser beam from the cleaved sample edge,and the reson...We report the coherent resonant emission of the exciton state in a single InAs quantum dot,embedded in a planar optical microcavity.The quantum dot is excited by a laser beam from the cleaved sample edge,and the resonant fluorescence is collected in the direction perpendicular to the excitation laser beam,so the residual laser scattering can be deeply suppressed.This experimental setup enables us to observe Rabi oscillation and a Mollow triplet with Rabi energy up to about 27μeV.展开更多
文摘在对In As单量子点施加流体静压的实验中,使用了带有压电陶瓷的连续加压装置,在低温连续施加流体静压的情况下,可以调节量子点单激子能量兰移约320 me V。在对不同流体静压下单激子发光的二阶关联函数测量之后,证明流体静压并不影响单激子发光的单光子特性。同时通过流体静压,可以实现量子点双激子态由反束缚态到束缚态的转变,并且给出了这一过程的偏振分辨光谱图。最后观察到单量子点精细结构劈裂随流体静压的增加而增加,而且精细结构劈裂的增加量可以达到约150μe V。
基金Supported by the National Natural Science Foundation of China under Grant Nos 60676054, 10734060 and 60625405, and the National Basic Research Programme of China under Grant No 2007CB924904, and the Knowledge Innovation Programme of Chinese Academy of Sciences under Grant No KJCX2.YW.W09-1.
文摘We report on the single photon emission from single InAs/GaAs self-assembled Stranski-Krastanow quantum dots up to 80 K under pulsed and continuous wave excitations. At temperature 8OK, the second-order correlation function at zero time delay, g^（2）（0）, is measured to be 0.422 for pulsed excitation. At the same temperature under continuous wave excitation, the photon antibunching effect is observed. Thus, our experimental results demonstrate a promising potential application of self-assembled InAs/GaAs quantum dots in single photon emission at liquid nitrogen temperature.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10474095 and 60625405
文摘Excitation power-dependent micro-photoluminescence spectra and photon-correlation measurement are used to study the optical properties and photon statistics of single InAs quantum dots. Exciton and biexciton emissions, whose photoluminescence intensities have linear and quadratic excitation power dependences, respectively, are identified. Under pulsed laser excitation, the zero time delay peak of second order correlation function corresponding to exciton emission is well suppressed, which is a clear evidence of single photon emission.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60676054, and the National Key Projects for Basic Research of China under Grant No 2007CB924904.
文摘We report a photoluminescence （PL） energy red-shift of single quantum dots （QDs） by applying an in-plane compressive uniaxial stress along the [110] direction at a liquid nitrogen temperature. Uniaxial stress has an effect not only on the confinement potential in the growth direction which results in the PL shift, but also on the cylindrical symmetry of QDs which can be reflected by the change of the full width at half maximum of PL peak. This implies that uniaxial stress has an important role in tuning PL energy and fine structure splitting of QDs.
基金Supported by the National Natural Science Foundation of China under Grant No 60676054, the Knowledge Innovation Project of Chinese Academy of Sciences （KJCX2.YW.W09-3）, and the National Basic Research Programme of China under Grant No 2007CB924904
文摘We investigate the temperature dependence of photoluminescence from single and ensemble InAs/GaAs quantum dots systematically. As temperature increases, the exciton emission peak for single quantum dot shows broadening and redshift. For ensemble quantum dots, however, the exciton emission peak shows narrowing and fast redshift. We use a simple steady-state rate equation model to simulate the experimental data of photoluminescence spectra. It is confirmed that carrier-phonon scattering gives the broadening of the exciton emission peak in single quantum dots while the effects of carrier thermal escape and retrapping play an important role in the narrowing and fast redshift of the exciton emission peak in ensemble quantum dots.
基金Project supported by the National Natural Science Foundations of China (Grant Nos O69C041001 and 2007CB924904)
文摘This paper studies the size dependence of biexciton binding energy in single quantum dots （QDs） by using atomic force microscopy and micro-photoluminescence measurements. It finds that the biexciton binding energies in the QDs show ＂binding＂ and ＂antibinding＂ properties which correspond to the large and small sizes of QDs, respectively. The experimental results can be well interpreted by the biexciton potential curve, calculated from the exciton molecular model and the Heitler London method.
基金Supported by the National Natural Science Foundation of China under Grant Nos 90921015,11074246.
文摘We report the coherent resonant emission of the exciton state in a single InAs quantum dot,embedded in a planar optical microcavity.The quantum dot is excited by a laser beam from the cleaved sample edge,and the resonant fluorescence is collected in the direction perpendicular to the excitation laser beam,so the residual laser scattering can be deeply suppressed.This experimental setup enables us to observe Rabi oscillation and a Mollow triplet with Rabi energy up to about 27μeV.
