量子点光电单量子态研究形成了单光子探测和光子发射两个方向上的技术机遇。其中基于量子点的共振放大结构（QD-RTD）被认为在单光子探测方面综合性能最佳，但受到光子数识别、工作温度两个关键性能的制约。单量子态项目（91121009）和（91021015）分别在能态构造和光电效应调控方面显现出突破它们的机遇。另一方面，项目（91121021）揭示了一种通过磁场调控电子态获得圆偏振光子源的新途径；而项目（91021015）也展示了更高品质光子晶体微腔的实现方法，二者结合可能形成一种强耦合圆偏振单光子源的新途径。为此，建议集成上述关联性强的项目基础，通过光子-电子微观量子态的构造和精细调控、量子效应的观测、原型器件的验证等环节的密切结合，一方面，实现QD-RTD光子数分辨和较高温度单光子探测；同时利用腔模-激子态-外场耦合效应，获得圆偏振态可控的高频单光子发射。

Studies on quantum dots (QDs) provide great opportunities in single photon detection as well as single circular polarized photon emission, which are the key technology for future quantum information processing. For single photon detection, the quantum-dot-resonant-tunneling-diode (QD-RTD) is evaluated as one of the most promising scheme but still suffering from the ultralow working temperature(~5K) and lack the capability to discriminate photon numbers. The progress of ongoing project (91121009) and (91021015) suggests that the barrier quantum dots (QDs)s can be overcome by novel design and careful control on electronic states in QD and QWs. Also project No. 91121021 disclosed a new way to emit circular polarized photons by modulating the spin of electrons in QDs. At the same time, project 91021015 depicts a way to grow high quality two dimensional photon crystal structures. Then a novel routine to get circular polarized photon emission can be realized by combining the strong coupling of cavity-exciton and the spin polarization on exciton in QD. In consequence, it is suggested to integrate the complementary advantages of the three ongoing projects. Through close cooperation among e-photon quantum state construction and manipulation, observation on photo-electric mechanism, as well as prototype with prototype device, it’s likely to, on the one hand, find the way to detect single photon with QD-RTD on liquid nitrogen temperature and be able to discriminate photon numbers, on the other hand to get high frequency circular polarized photon from a QD emitter.