Atatüre Mete, Dreiser Jan, Badolato Antonio, Högele Alexander, Karrai Khaled, Imamoglu Atac
Institute of Quantum Electronics, ETH Zurich, CH-8093 Zurich, Switzerland.
Science. 2006 Apr 28;312(5773):551-3. doi: 10.1126/science.1126074. Epub 2006 Apr 6.
We have demonstrated laser cooling of a single electron spin trapped in a semiconductor quantum dot. Optical coupling of electronic spin states was achieved using resonant excitation of the charged quantum dot (trion) transitions along with the heavy-light hole mixing, which leads to weak yet finite rates for spin-flip Raman scattering. With this mechanism, the electron spin can be cooled from 4.2 to 0.020 kelvin, as confirmed by the strength of the induced Pauli blockade of the trion absorption. Within the framework of quantum information processing, this corresponds to a spin-state preparation with a fidelity exceeding 99.8%.
我们已经展示了对捕获在半导体量子点中的单个电子自旋进行激光冷却。利用带电量子点（三重态激子）跃迁的共振激发以及重轻空穴混合实现了电子自旋态的光学耦合，这导致自旋翻转拉曼散射的速率虽弱但有限。通过这种机制，电子自旋可以从4.2开尔文冷却到0.020开尔文，三重态激子吸收的诱导泡利阻塞强度证实了这一点。在量子信息处理框架内，这对应于保真度超过99.8%的自旋态制备。
