Optical measurement of temperature dependent antiferromagnetic resonance on CrSBr*

NV centers in diamond are single-spin color centers whose photoluminescence (PL)depends on their spin-state populations. This spin population can be hyperpolarized into the m_s=0 state. Driven antiferromagnetic resonance (AFMR) modes decays into high frequency magnons, and multi-magnon scattering can generate electromagnetic radiation at frequencies matching the NV center magnetic resonance frequency thus enhancing spin relaxation that modifies the spin state populations and hence PL intensity. CrSBr is a van der Waals antiferromagnet with promising magnetic properties for memory devices. Below its Neel temperature (132K), CrSBr exhibits intralery ferromagnetic order; a weaker interlayer antiferromagnetic exchange coupling leads to AF order. The weakness of the AF coupling leads to AF resonant frequencies in the tens of GHz range. We present results on the optical measurement of this temperature dependent AFMR as measured with NV color centers.