Ultralong quantum optical storage using reversible inhomogeneous spin ensembles with an optical locking method

Ultralong Photon Echo Storage Using Optical Locking

An ultralong photon storage with more than 50% retrieval efficiency is presented in the three-pulse photon echoes by using a pair of control pulses, where the control pulses play to freeze atoms dephasing process conditionally by transferring excited atoms to an auxiliary state and returning them back later. The observed photon echo decay time much longer than the spin homogeneous decay time is potential for long distance quantum communications.

Ultralong Efficient Photon Storage Using Optical Locking

For the last decade quantum memories have been intensively studied for potential applications to quantum information and communications using atomic and ionic ensembles. With the importance of a multimode storage capability in quantum memories, on-demand control of reversible inhomogeneous broadening of an optical medium has been broadly investigated recently. However, the photon storage time in these researches is still too short to apply for long-distance quantum communications. In this paper, we demonstrate new physics of spin population decay dependent ultralong photon storage method, wher…

On-demand control of photon echoes far exceeding the spin coherence constraint via coherence swapping between optical and spin transitions

Using on-demand coherence conversion via optical locking in conventional stimulated (three-pulse) photon echoes, ultralong, ultraefficient photon storage has been observed in a rare-earth Pr3+ doped Y2SiO5, where storage time is several orders of magnitude longer and retrieval efficiency is enhanced by fifty times. Compared with the same method applied to two-pulse photon echoes for a rephasing halt, use of spectral grating in the stimulated photon echoes offers a phase-independent coherence conversion between optical and spin states. Eventually an ultralong spin population decay-dependent pho…

The basic principles to construct a generalized state-locking pulse field and simulate efficiently the reversible and unitary halting protocol of a universal quantum computer

It has been shown (Arxiv: quant-ph/0507236) that a universal quantum computer could be powerful enough to solve efficiently the quantum search problem, and the reversible and unitary halting protocol based on the state-locking pulse field is the key component to construct the efficient quantum search processes, while the state-locking pulse field is the key component to generate the reversible and unitary halting protocol. In this paper the reversible and unitary halting protocol and the generalized state-locking pulse field have been extensively investigated theoretically. The basic principle…

通过周期驱动动态锁定相互作用自旋系统

Dynamic locking of an interacting spin system via periodic driving

本文研究了通过周期驱动偏离共振条件动态锁定自旋系统的方法，展示了偏移和脉冲结构生成的有效Rabi场，为多体系统控制提供了新途径，包括Zeeman和偶极序的可逆转换及非共振条件下的异自旋极化转移。

The unitary dynamical state-locking process, the HSSS quantum search process, and the quantum-computing speedup theory

A unitary dynamical state-locking (UNIDYSLOCK) process is a unitary process that can transform two orthogonal states to two non-orthogonal states. Its inverse process, i.e., the QUANSDAM process could realize an exponential QC speedup in solving an unstructured search problem in the quantum-computing (QC) speedup theory (X. Miao, arXiv:1105.3573 [quant-ph] (2011)). In this paper the principle of how a UNIDYSLOCK process works is described on the basis of the QC speedup theory. A UNIDYSLOCK process does not exist at all in pure quantum mechanics. That it can change the quantum-state difference …