Real-time zero-field magnetometry using a single NV center coupled to a first-shell 13C nuclear spin in diamond

Pralekh Dubey (IISER Bhopal, India)

LinkedIn: Pralekh Dubey

Abstract: Nitrogen-vacancy (NV) centers in diamond are robust and versatile solid-state defects that serve as optically addressable spin qubits under ambient conditions. When coupled to nearby first-shell 13C nuclear spins, they form a hybrid electron-nuclear spin system with rich hyperfine structure, which can also serve as a quantum register for NMR, quantum information processing and sensing applications 1. Here, we explore this coupled system in the context of zero-field quantum sensing 2. We demonstrate real-time zero-field magnetometry using first-shell 13C-coupled single NV centers in diamond. The strong hyperfine interaction (~130MHz) 3 with the proximal 13C spin lifts the degeneracy of the NV spin transitions and provides an intrinsic bias in the absence of an external magnetic field 4,5. Selective addressing and tracking of individual transitions under zero-field conditions, allows time-varying magnetic fields (up to few Hz) to be monitored in real time. This work highlights how coupled NV-13C spin systems are valuable for real-time zero-field magnetometry, with possible extension to other solid-state systems.