Single-Shot Readout and Weak Measurement of a Tin-Vacancy Qubit in Diamond
Eric I. Rosenthal, Souvik Biswas, Giovanni Scuri, Hope Lee, Abigail Stein, Hannah C. Kleidermacher, Jakob Grzesik, Alison E. Rugar, Shahriar Aghaeimeibodi, Daniel Riedel, Michael Titze, Edward S. Bielejec, Joonhee Choi, Christopher P. Anderson, Jelena Vučković
Abstract
The negatively charged tin-vacancy center in diamond ( <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mrow> <a:msup> <a:mrow> <a:mi>SnV</a:mi> </a:mrow> <a:mrow> <a:mo>−</a:mo> </a:mrow> </a:msup> </a:mrow> </a:math> ) is an emerging platform for building the next generation of long-distance quantum networks. This is due to the <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"> <c:mrow> <c:msup> <c:mrow> <c:mi>SnV</c:mi> </c:mrow> <c:mrow> <c:mo>−</c:mo> </c:mrow> </c:msup> </c:mrow> </c:math> ’s favorable optical and spin properties including bright emission, insensitivity to electronic noise, and long spin coherence times at temperatures above 1 K. Here, we demonstrate measurement of a single <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"> <e:mrow> <e:msup> <e:mrow> <e:mi>SnV</e:mi> </e:mrow> <e:mrow> <e:mo>−</e:mo> </e:mrow> </e:msup> </e:mrow> </e:math> electronic spin with a single-shot readout fidelity of 87.4%, which can be further improved to 98.5% by conditioning on multiple readouts. In the process, we develop understanding of the relationship between strain, magnetic field, spin readout, and microwave spin control. We show that high-fidelity readout is compatible with rapid microwave spin control, demonstrating a favorable parameter regime for use of the <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"> <g:mrow> <g:msup> <g:mrow> <g:mi>SnV</g:mi> </g:mrow> <g:mrow> <g:mo>−</g:mo> </g:mrow> </g:msup> </g:mrow> </g:math> center as a high-quality spin-photon interface. Finally, we use weak quantum measurement to study measurement-induced dephasing; this illuminates the fundamental interplay between measurement and decoherence in quantum mechanics, and provides a universal method to characterize the efficiency of color-center spin readout. Taken together, these results overcome an important hurdle in the development of the <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"> <i:mrow> <i:msup> <i:mrow> <i:mi>SnV</i:mi> </i:mrow> <i:mrow> <i:mo>−</i:mo> </i:mrow> </i:msup> </i:mrow> </i:math> -based quantum technologies and, in the process, develop techniques and understanding broadly applicable to the study of solid-state quantum emitters. Published by the American Physical Society 2024