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arXiv · 2002.03669

Electron Spin Resonance spectroscopy with femtoliter detection volume

Vishal Ranjan·Sebastian Probst·Bartolo Albanese·Thomas Schenkel·Denis Vion·Daniel Esteve·John Morton·Patrice Bertet
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Abstract

We report electron spin resonance measurements of donors in silicon at millikelvin temperatures using a superconducting $LC$ planar micro-resonator and a Josephson Parametric Amplifier. The resonator includes a nanowire inductor, defining a femtoliter detection volume. Due to strain in the substrate, the donor resonance lines are heavily broadened. Single-spin to photon coupling strengths up to $\sim 3~\text{kHz}$ are observed. The single shot sensitivity is $120 \pm 24~$spins/Hahn echo, corresponding to $\approx 12 \pm 3$~spins$/\sqrt{\text{Hz}}$ for repeated acquisition.

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Vishal Ranjan, Sebastian Probst, Bartolo Albanese, Thomas Schenkel, Denis Vion, Daniel Esteve, John Morton, Patrice Bertet. 2020-02-10. Electron Spin Resonance spectroscopy with femtoliter detection volume. https://doi.org/10.1063/5.0004322

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