Polarization Selective Quantum Sensing of Spin Wave

Nitrogen-vacancy (NV) center-based quantum sensing has rapidly advanced over the past decade, finding applications in spintronics, biology, and condensed matter physics. However, one key property of this spin-triplet system — its selective sensitivity to polarization of magnetic fields — remains largely underexplored in sensing applications. This underutilized characteristic of NV center holds potential for detecting high-frequency magnetic phenomena and enabling new capabilities in nanoscale magnetometry.

In this dissertation, I present the development of a quantum sensing platform based on NV centers, designed for high-sensitivity, high-spatial resolution detection of magnetic fields. We exploit the NV center’s polarization-selective response to detect circularly polarized stray fields generated by spin waves in magnetic thin film. The dispersion relations of spin wave in ferromagnetic thin film are inherently anisotropic, resulting in non-reciprocal propagation behaviors that remain insufficiently characterized experimentally. The NV center’s polarization sensitivity provides a unique, powerful tool for probing these chiral spin-wave properties with nanoscale spatial resolution and excellent sensitivity.

By advancing polarization-sensitive quantum sensing techniques, this work contributes to a deeper understanding of chiral spin-wave dynamics and expands the utility of NV-based quantum sensors for detecting dynamic and high-frequency magnetic fields. These developments open new pathways for exploring a wider range of physical phenomena, potentially enabling the characterization of magnetic textures, high-frequency magnetic excitations in spintronic and quantum devices.