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Published on: November 11, 2013
Energy relaxation time between macroscopic quantum levels in a superconducting persistent-current qubit
Yang Yu1, D Nakada, Janice C Lee
1Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Abstract:
We measured the intrawell energy relaxation time tau(d) approximately 24 micros between macroscopic quantum levels in the double well potential of a Nb persistent-current qubit. Interwell population transitions were generated by irradiating the qubit with microwaves. Zero population in the initial well was then observed due to a multilevel decay process in which the initial population relaxed to lower energy levels during the driven transitions. The decoherence time, estimated from tau(d) within the spin-boson model, is about 20 micros for this configuration with a Nb superconducting qubit.
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