Relation between quantum NOT gate speed and asymmetry of the potential of RF-SQUID  

作　　者：嵇英华 蔡十华 胡菊菊 

机构地区：[1]Department of Physics,Jiangxi Normal University [2]Key Laboratory of Optoelectronic & Telecommunication of Jiangxi

出　　处：《Chinese Physics B》2008年第2期440-444,共5页中国物理B（英文版）

基　　金：Project supported by the Science and Technology Research Foundation of the Education Department of Jiangxi Province,China(Grant No 200592)

摘　　要：This paper investigates the relationship between the speed of a quantum not gate and the asymmetry of the potential in an interactive system formed by a two-level RF-SQUID qubit and a classical microwave pulse. The RFSQUID is characterized by an asymmetric double well potential which gives rise to diagonal matrix elements that describe the interaction of the SQUID with the microwave pulse. And the diagonal matrix elements account for the interaction of the microwave pulse with the SQUID. The results indicate that, when the angular frequency of the microwave field is chosen as near resonate with the transition （0） ←→ （1）, i.e. ω1 -ω0 ≈ ωm, （1） the gate speed is decided by three factors, the Rabi frequency, the difference of the diagonal matrix elements between the two levels, and the angular frequency of the applied microwave pulse ωm; （2） the gate speed descends when the asymmetry of the potential is considered.This paper investigates the relationship between the speed of a quantum not gate and the asymmetry of the potential in an interactive system formed by a two-level RF-SQUID qubit and a classical microwave pulse. The RFSQUID is characterized by an asymmetric double well potential which gives rise to diagonal matrix elements that describe the interaction of the SQUID with the microwave pulse. And the diagonal matrix elements account for the interaction of the microwave pulse with the SQUID. The results indicate that, when the angular frequency of the microwave field is chosen as near resonate with the transition （0） ←→ （1）, i.e. ω1 -ω0 ≈ ωm, （1） the gate speed is decided by three factors, the Rabi frequency, the difference of the diagonal matrix elements between the two levels, and the angular frequency of the applied microwave pulse ωm; （2） the gate speed descends when the asymmetry of the potential is considered.

关 键 词：gate speed asymmetry microwave pulse RF-SQUID 

分 类 号：O413.1[理学—理论物理]