Nuclear spin dynamics of driven VB centers

Adalbert I. Tibiássy
Eötvös Lordán Scientific University, Budapest, Hungary _______________________________________

The VB(-) spin qubit in boron nitride is a promising platform for quantum sensing in low-dimensional systems. While VB(-) is embedded in a dense bath of nuclear spins, their role in electron spin dynamics and potential nuclear spin-related applications remains unexplored. In this presentation, I report on our theoretical and numerical study of electron-nuclear spin dynamics on short timescales in a closed VB(-) system with four nuclear spins, under varying drive frequencies and static magnetic field strengths. Using nth-order perturbation theory to compute transition matrix elements between different state pairs, I demonstrate that hyperfine interactions lift fundamental degeneracies in nuclear spin transitions, enabling individual addressing of each hyperfine energy level (see Fig. 1). Furthermore, under a strong parallel microwave drive, we observe multiphoton transitions at half and one-third of the first-order optically detected magnetic resonance (ODMR) transition energy frequency. Our simulations highlight the essential role of nuclear spins in these transitions. These findings provide deeper insights into the tunability and complexity of spin systems in boron nitride, paving the way for novel quantum applications.

Email: tibiassy.adalbert@gmail.com