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Published on: June 28, 2018
Force detected electron spin resonance at 94 GHz
Paul A S Cruickshank1, Graham M Smith
1School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9SS, Scotland.
The Review of Scientific Instruments
|May 17, 2007
Summary
Force Detected Electron Spin Resonance (FDESR) measurements were performed at 3.2 T, achieving record high magnetic fields. This advancement enhances sensitivity and spectral resolution for detecting unpaired electrons.
Area of Science:
- Physics
- Materials Science
- Chemistry
Background:
- Force Detected Electron Spin Resonance (FDESR) detects unpaired electrons via force changes on a resonator due to modulated sample magnetization.
- While offering high sensitivity and spatial resolution, FDESR faces challenges in concentration sensitivity and spectral interpretation.
- Operating at higher magnetic fields can improve sample magnetization and g-factor resolution, potentially enhancing FDESR performance.
Purpose of the Study:
- To present Force Detected Electron Spin Resonance (FDESR) measurements at unprecedentedly high magnetic fields.
- To investigate the feasibility and benefits of high-field FDESR for improved sensitivity and spectral resolution.
- To demonstrate FDESR on the organic conductor (fluoranthene)(2)PF(6) at 3.2 T and 93.5 GHz.
Main Methods:
- Utilized a magnet-on-cantilever approach for FDESR measurements.
- Employed a high-anisotropy microwave ferrite as the magnetic field gradient source.
- Implemented cyclic saturation to modulate sample magnetization at the cantilever's fundamental frequency.
Main Results:
- Successfully conducted FDESR measurements at 3.2 T (93.5 GHz), believed to be the highest field reported to date.
- Demonstrated the capability of high-field FDESR for studying electron spin properties.
- The study provides new data on the organic conductor (fluoranthene)(2)PF(6) at millimeter-wave frequencies.
Conclusions:
- High-field operation significantly enhances Force Detected Electron Spin Resonance (FDESR) capabilities.
- The presented results pave the way for improved sensitivity and spectral resolution in FDESR spectroscopy and imaging.
- Further exploration of high-field FDESR is warranted for advanced materials characterization.
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