Time-domain measurements of quasiparticle tunneling rates in a single-Cooper-pair transistor

We have measured, in real time, individual quasiparticle tunneling in a single-Cooper-pair transistor, using rf reflectometry on the supercurrent branch. We have extracted the even-to-odd and odd-to-even transition rates directly by analyzing the distributions of dwell times in the even and odd states of the transistor. We discuss both the measurement and analysis techniques and report on the temperature and gate dependence of the quasiparticle tunneling rates.