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arXiv · 2506.00345

Strain Enhanced Spin Readout Contrast in Silicon Carbide Membranes

Haibo Hu·Guodong Bian·Ailun Yi·Chunhui Jiang·Junhua Tan·Qi Luo·Bo Liang·Zhengtong Liu·Xinfang Nie·Dawei Lu·Shumin Xiao·Xin Ou·Adam Gali·Yu Zhou·Qinghai Song
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Abstract

Quantum defects in solids have emerged as a transformative platform for advancing quantum technologies. A key requirement for these applications is achieving high-fidelity single-spin readout, particularly at room temperature for quantum biosensing. Here, we demonstrate through ab initio simulations of a primary quantum defect in 4H silicon carbide that strain is an effective control parameter for significantly enhancing readout contrast. We validate this principle experimentally by inducing local strain in silicon carbide-on-insulator membranes, achieving a readout contrast exceeding 60% while preserving the favorable coherence properties of single spins. Our findings establish strain engineering as a powerful and versatile strategy for optimizing coherent spin-photon interfaces in solid-state quantum systems.

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Haibo Hu, Guodong Bian, Ailun Yi, Chunhui Jiang, Junhua Tan, Qi Luo, Bo Liang, Zhengtong Liu, Xinfang Nie, Dawei Lu, Shumin Xiao, Xin Ou, Adam Gali, Yu Zhou, Qinghai Song. 2025-05-31. Strain Enhanced Spin Readout Contrast in Silicon Carbide Membranes. https://arxiv.org/abs/2506.00345

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