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arXiv:2602.22301

Atomic-Scale Quantum Control of Single Spin Defects in a Two-Dimensional Semiconductor

Kwan Ho Au-Yeung, Wantong Huang, Johanna Matusche, Paul Greule, Jonas Arnold, Lovis Hardeweg, Máté Stark, Luise Renz, Affan Safeer, Daniel Jansen, Thomas Michely, Jeison Fischer, Wolfgang Wernsdorfer, Christoph Sürgers, Hannu-Pekka Komsa, Johannes Schwenk, Wouter Jolie, Philip Willke

cond-mat.mes-hallcond-mat.mtrl-sciquant-phSubmitted Feb 25, 2026• Announced Feb 26, 2026

Abstract

Individual spin defects in solids are promising building blocks for quantum technologies, but their deterministic creation, individual addressability, and operation near surfaces remain major challenges. Two-dimensional materials provide an attractive alternative, as their single-layer thickness enables direct atomic-scale access to defect states. Here, we demonstrate single-spin control of solid-state defects in a two-dimensional semiconductor by a combination of scanning tunneling microscopy and electron spin resonance. We create and manipulate individual sulfur vacancies and carbon substitution defects in monolayer molybdenum disulfide and characterize their spin dynamics, including coherent control, at the single-defect level. Using atomic manipulation, we further engineer and probe spin-spin interactions between defect pairs. Our results demonstrate deterministic creation, addressability, coherent manipulation, and controlled coupling of individual spin defects within a single experimental platform. This establishes atomically engineered spin defects in two-dimensional semiconductors as a versatile class of controllable solid-state quantum systems and opens a route towards tailored quantum sensing experiments.

Comments: 30 pages, 4 figures in the main text, 10 supplementary figures

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learning

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assisted design and integrated experiment

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theory feedback loops. By connecting microscopic quantum states to mesoscopic excitations and macroscopic device architectures, this Roadmap outlines a materials-centric framework for integrating coherent quantum functionalities and positions 2D materials as foundational building blocks for next-generation quantum technologies.

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