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arXiv · 2108.13663

Preparation and Readout of Multielectron High-Spin States in a Gate-Defined GaAs/AlGaAs Quantum Dot

H. Kiyama·K. Yoshimi·T. Kato·T. Nakajima·A. Oiwa·S. Tarucha
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Abstract

We report the preparation and readout of multielectron high-spin states, a three-electron quartet, and a four-electron quintet, in a gate-defined GaAs/AlGaAs single quantum dot using spin filtering by quantum Hall edge states coupled to the dot. The readout scheme consists of mapping from multielectron to two-electron spin states and a subsequent two-electron spin readout, thus obviating the need to resolve dense multielectron energy levels. Using this technique, we measure the relaxations of the high-spin states and find them to be an order of magnitude faster than those of low-spin states. Numerical calculations of spin relaxation rates using the exact diagonalization method agree with the experiment. The technique developed here offers a new tool for the study and application of high-spin states in quantum dots.

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H. Kiyama, K. Yoshimi, T. Kato, T. Nakajima, A. Oiwa, S. Tarucha. 2021-08-31. Preparation and Readout of Multielectron High-Spin States in a Gate-Defined GaAs/AlGaAs Quantum Dot. https://doi.org/10.1103/physrevlett.127.086802

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