Ultra-low frequency EPR using longitudinal detection and fictitious-field modulation

J Magn Reson. 2020 Dec:321:106855. doi: 10.1016/j.jmr.2020.106855. Epub 2020 Oct 22.

Abstract

When viewed in a rotating frame of reference, a transverse-plane radiofrequency (RF) field manifests as a longitudinal field component called the fictitious field. By modulating the RF field and thus the fictitious field, detectable longitudinal magnetization patterns have previously been shown to be measurable. By combining fictitious-field modulation and longitudinal detection, here we demonstrate EPR spectroscopy and one-dimensional imaging in a custom-built longitudinal detection system operating at an ultra-low frequency (24 MHz) for detecting electron spins with short (~nanoseconds) relaxation times. Simultaneous transmit and receive with low transmitter leakage level (~80 dB isolation) is also demonstrated.

Keywords: Electron paramagnetic resonance; Fictitious field; Iron-oxide nanoparticles; Longitudinal detection; Simultaneous transmit and receive; Spectroscopy.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Dextrans / chemistry*
  • Electron Spin Resonance Spectroscopy / instrumentation
  • Electron Spin Resonance Spectroscopy / methods*
  • Equipment Design
  • Magnetite Nanoparticles / chemistry*
  • Radio Waves
  • Signal Processing, Computer-Assisted

Substances

  • Dextrans
  • Magnetite Nanoparticles
  • ferumoxides