Zener enhancement of quantum tunneling in a two-level superconducting circuit.
نویسندگان
چکیده
We have investigated the macroscopic quantum tunneling (MQT) of the phase across a Josephson junction embedded in a superconducting circuit. This system is equivalent to a spin 1/2 particle in a potential energy well. The MQT escape rate of such a particle was recently predicted to be strongly modified when a crossing of its inner Zeeman levels occurs while tunneling. In this regime, we observe a significant enhancement of the MQT rate and compare it to theory.
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ورودعنوان ژورنال:
- Physical review letters
دوره 94 5 شماره
صفحات -
تاریخ انتشار 2005