Applied Physics Letters
Inductive-detection electron-spin resonance spectroscopy with 65 spins/root Hz sensitivity
Sebastian Probst, Audrey Bienfait, Philippe Campagne-Ibarcq, Jarryd J. Pla, Bartolo Albanese, Jfds Barbosa, Thomas Schenkel, D. Vion, D. Estève, Klaus Mølmer, John J. L. Morton, Reinier Heeres, Patrice Bertet
Abstract
We report electron spin resonance spectroscopy measurements performed at millikelvin temperatures in a custom-built spectrometer comprising a superconducting micro-resonator at 7 GHz and a Josephson parametric amplifier. Owing to the small (∼10−12λ3∼10−12λ3) magnetic resonator mode volume and to the low noise of the parametric amplifier, the spectrometer's single shot sensitivity reaches 260 ± 40 spins/echo translating into 65±10 spins/Hz⎯⎯⎯⎯⎯√65±10 spins/Hz for repeated acquisition.