Dephasing of Exchange-coupled Spins in Quantum Dots for Quantum Computing

• URL: http://arxiv.org/abs/2109.02261v1
• Date: Mon, 6 Sep 2021 06:38:20 GMT
• Title: Dephasing of Exchange-coupled Spins in Quantum Dots for Quantum Computing
• Authors: Peihao Huang
• Abstract summary: A spin qubit in semiconductor quantum dots holds promise for quantum information processing. We report progress on spin dephasing of two exchange-coupled spins in a double quantum dot.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: A spin qubit in semiconductor quantum dots holds promise for quantum information processing for scalability and long coherence time. An important semiconductor qubit system is a double quantum dot trapping two electrons or holes, whose spin states encode either a singlet-triplet qubit or two single-spin qubits coupled by exchange interaction. In this article, we report progress on spin dephasing of two exchange-coupled spins in a double quantum dot. We first discuss the schemes of two-qubit gates and qubit encodings in gate-defined quantum dots or donor atoms based on the exchange interaction. Then, we report the progress on spin dephasing of a singlet-triplet qubit or a two-qubit gate. The methods of suppressing spin dephasing are further discussed. The understanding of spin dephasing may provide insights into the realization of high-fidelity quantum gates for spin-based quantum computing.

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