Nanoscale NV-detected Electron Spin Resonance at 115 GHz and 4.2 Tesla

The nitrogen-vacancy (NV) center is a promising candidate for single-spin electron spin resonance (ESR). NV-detected ESR enables ESR analysis for paramagnetic spins with sensitivity of a single spin. We have recently shown that the spectral resolution of NV-detected ESR is improved by carefully adjusting microwave (MW) pulse duration and intensity [1]. Pulsed ESR spectroscopy at high magnetic fields offers higher spectral resolution and greater spin polarization than measurements at lower magnetic fields. However, the shift to high fields requires a high frequency MW source whose output power is often much lower than that of a low frequency MW source. This results in incomplete population inversion due to limited excitation bandwidths and spin relaxation. Within this talk we present our development and application of adiabatic pulses at 115 GHz to overcome this challenge. We utilize these pulses to control the spin states of single NV centers and to perform ESR using a single NV center at a field of 4.2 Tesla [2].

[1] B. Fortman and S. Takahashi, J. Phys. Chem. A.123, (2019).
[2] B. Fortman, J. Pena, and S. Takahashi, In Preparation. (2019).