2015/03/31 by D. T. McClure, Hanhee Paik, L. S. Bishop +3 · 2 citations
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1103/physrevapplied.5.011001
published as Phys. Rev. Applied 5, 011001 (2016)
arxiv created 2015/05/22 · arxiv updated 2016/02/03
Using a circuit QED device, we demonstrate a simple qubit measurement pulse shape that yields fast ring-up and ring-down of the readout resonator regardless of the qubit state. The pulse differs from a square pulse only by the inclusion of additional constant-amplitude segments designed to effect a rapid transition from one steady-state population to another. Using a Ramsey experiment performed shortly after the measurement pulse to quantify the residual population, we find that compared to a square pulse followed by a delay, this pulse shape reduces the timescale for cavity ring-down by more than twice the cavity time constant. At low drive powers, this performance is achieved using pulse parameters calculated from a linear cavity model; at higher powers, empirical optimization of the pulse parameters leads to similar performance.