Macroscopic quantum tunneling in a dc SQUID
Macroscopic quantum tunneling in a dc SQUID
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直流 SQUID 中的宏观量子隧道效应
DOI：
10.1007/bf00685404
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发表时间：
1986
影响因子：
2
通讯作者：
YongJu Chen
中科院分区：
文献类型：
--
作者：
YongJu Chen
将宏观量子隧穿理论应用于电流偏置的dc SQUID，其动力学可以用具有耗散环境的二维力学系统来描述。基于Caldeira和Leggett提出的唯象模型，耗散环境被表示为一组耦合到系统的谐振子。在对环境自由度进行积分后，找到了二维系统的有效欧氏作用量。该作用被用来提供dc SQUID的量子隧穿率形式。在一定条件下，隧穿率降低到一个单一的电流偏置约瑟夫森结的有效临界电流可调。
The theory of macroscopic quantum tunneling is applied to a current-biased dc SQUID whose dynamics can be described by a two-dimensional mechanical system with a dissipative environment. Based on the phenomenological model proposed by Caldeira and Leggett, the dissipative environment is represented by a set of harmonic oscillators coupling to the system. After integrating out the environmental degrees of freedom, an effective Euclidean action is found for the two-dimensional system. The action is used to provide the quantum tunneling rate formalism for the dc SQUID. Under certain conditions, the tunneling rate reduces to that of a single current-biased Josephson junction with an adjustable effective critical current.