Ambient pressure response of spin defects in two-dimensional materials

Spin defects in two-dimensional (2D) materials emerge as promising platforms for quantum sensing applications. The thin-film characteristic of these materials is their most unique feature, distinguishing them from traditional three-dimensional (3D) materials. This feature is particularly suitable for transferring ambient (gas) pressure to internal strain in the 2D material, which can be quantitatively detected <i>via</i> spin defects such as the negatively charged boron vacancy (V_B^-) in 2D hexagonal boron nitride (hBN). By designing a sealed structure featuring a specific hBN suspension and generating (V_B^-) spin defects by ion implantation, we experimentally examined this kind of ambient pressure sensor. We established the relationship between external pressure and the energy-level shift of spin defects. Our study is the first to demonstrate a quantum sensor based on spin defects in 2D materials designed for ambient pressure measurements, which is of great significance for future quantum sensing application.