腔耦合量子点系统的非常规几何量子计算

J4 ›› 2009, Vol. 26 ›› Issue (4): 431-436.

腔耦合量子点系统的非常规几何量子计算

张刚¹ 董萍²

1 皖西学院数理系，安徽，六安 237012;
2 合肥师范学院物理与电子工程系，安徽，合肥，230061

收稿日期:2009-04-23 修回日期:2009-05-11 出版日期:2009-07-28 发布日期:2009-06-29
通讯作者: 张刚（1975-）博士，皖西学院数理系讲师，研究方向：几何量子计算。 E-mail: zhanggang@wxc.edu.cn
基金资助:
国家自然科学基金（60678022，10704001）、安徽省教育厅自然科学基金（kj2009A048Z）

Unconventional geometric quantum computation with quantum-dot spin qubits inside a cavity

ZHANG Gang¹ , DONG Ping²

1Department of Physics and Mathematics, West Anhui,Uiversity, Lu'an , 237012, China;
2 Department of Physics, Hefei teacher college, Hefei,230061, China

Received:2009-04-23 Revised:2009-05-11 Published:2009-07-28 Online:2009-06-29

摘要/Abstract

摘要：

提出了在量子点与腔相互作用系统中，利用双拉曼过程来实现非常规几何量子逻辑门方案。在本方案中，所有的演化本身与腔场态无关，因而对热场是不敏感的。在总位相中既包含有几何位相,又包含有动力学位相,但它的确仅依赖于量子态演化的整体几何特征。通过调节耦合常数和失谐量来选择我们所要的量子控制门，在实际的操作中不需要考虑消除动力学相位问题因而易于操作，且避免因消除动力学相位引入的误差。

关键词: 几何量子计算, 量子点, 拉曼过程

Abstract:

A scheme for realizing unconventional geometric quantum logical gates with quantum dots in a microcavity, via double channels Raman interactions, is introduced. In the scheme, all of the operations are independent on the state of cavity mode, and thus insensitive to the thermal cavity field states. The total accumulate phase includes both geometric and dynamic phases, but it still depends only on global features of the process. The required quantum gates can be obtained by adjusting coupling constant and detunings. They are relatively easy in implementation by waive the needs of eliminating dynamic phases, and can reach higher fidelity by avoiding the additional errors in the process of eliminating dynamic phases.

Key words: geometric quantum computation, quantum dot, Raman interaction

张刚董萍. 腔耦合量子点系统的非常规几何量子计算[J]. J4, 2009, 26(4): 431-436.

ZHANG Gang, DONG Ping. Unconventional geometric quantum computation with quantum-dot spin qubits inside a cavity[J]. J4, 2009, 26(4): 431-436.

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