【摘要】 如何利用实际的物理系统存贮光子的量子信息 ,是当前量子计算和量子通信研究的核心问题之一 .近几年来 ,人们从理论和实验两个方面探讨了利用自由原子系综作为量子记忆体的可能性 .最近 ,基于固定于格点上Λ型“原子”系综的准自旋波激发的研究 ,我们提出了实现光子信息量子存贮的新方案 .这个方案的目标是为了克服自由原子系综量子存贮方案中存在的量子态漏损诱导退相干的致命问题 .在研究过程中 ,作者发现了系综型量子记忆体中隐藏动力学的对称性和其绝热暗态演化的选择定则 .为了使读者能确切地了解这个工作的意义 ,文章除了报道这个发表在PhysicalReviewLetters (2 0 0 3,91:14 790 3)的研究工作外 ,还扼要地介绍这个方案建立的前期关于原子系综对称集体激发的系列工作 .更多还原

【Abstract】 We present a new method for the storage of quantum information of photons based on the quasi-spin wave excitation of Λ-system atoms fixed at the sites of a lattice. The aim of this protocol is to avoid the disadvantage of the quantum memory scheme based on free atom ensembles, where decoherence is induced by quantum leakage of the collective state. In particular, we have discovered a universal dynamic symmetry hidden in various ensemble-based quantum storage schemes and a selectivity rule for the adiabatic dark state evolution. To understand the significance of this work we also give a brief overview of our earlier studies on collective symmetric excitons in quantum ensembles, which is necessary for our new quantum memory scheme.更多还原