基于微腔中自生长量子点的量子光信息存储

Quantum Light Memory Using Quantum Dot Spins in Microdisk Cavity

提出一个基于微型圆盘光学谐振腔(microdisk structure cavity)中自生长量子点的量子光信号存储方案,该方案利用量子光场和量子点系综自旋态之间的Raman过程来实现长时间的量子光信号存储.该方案的主要优势在于:使用全光学Raman过程来耦合光信号和腔中量子点的导带能级,使系统有可能存在较长的相干时间.此外,这种微腔中自生长量子点的工艺比较成熟,使该方案便于实验上实现、控制和大规模集成.

This paper studies a solid-state quantum circuit in which an ensemble of self-assembled quantum dots in a microdisk cavity is served as long-lived quantum light memory. It is shown that, via the laser coupling Raman process, coherent transfer between the light field （qubits） and the ensemble spin states of the quantum dots is efficient and fast. Coherence properties of the system are analyzed, which enables one to obtain a long coherence time. It can be used as a storage cell with practical applications in the future.