Affiliation:
1. Department of Physics, University of Wisconsin-Madison 1 , Madison, Wisconsin 53706, USA
2. University of New South Wales 2 , Sydney, New South Wales 2052, Australia
Abstract
A primary method of reading out a quantum dot hybrid qubit involves projection of the logical basis onto distinct charge states that are readily detected by an integrated charge sensing dot. However, in the simplest configuration, the excited charge state decays rapidly, making a single-shot readout challenging. Here, we demonstrate a readout procedure where the qubit excited state is latched to a metastable charge configuration whose lifetime is tunnel-rate limited, persisting here as long as 2.5 ms. Additionally, we show that working in the (4,1)–(3,2) charge configuration enables a latched readout window that is larger and more tunable than typical charge configurations, because the size of the readout window is determined by an orbital splitting rather than a valley splitting.
Funder
Army Research Office
National Science Foundation
the Department of Defense
Subject
Physics and Astronomy (miscellaneous)