4-coil air-core magnet for 90-G center field with z-gradient coils installed
The homogeneity is within +-40 ppm over a 15-cm diameter sphere.
An NMR-style reflection resonator is handy for very small samples at 250 MHz
Electron spin echoes of trityl radicals can be used in EPR imaging
A cross-loop resonator is under development for use in this cryostat to explore the utility of 250 MHz EPR for ESEEM studies of proteins and for relaxation measurements.
x- and y- gradient coils can be added
The cross-loop resonator can be operated with a horizontal sample loop as in this version, which was designed for in vivo studies of mice.
Deadtimes as short as 200 ns have been achieved using the cross loop resonator and dynamic Q-spoiling
Two pulsed RF amplifiers have been produced that have good fidelity for short pulses and turn off to within 10-20 dB of thermal noise level in ca. 80 ns after the pulse.
Vector network analyzers are used to measure the characteristics of resonators such as the cross loop resonators shown under construction, and completed.
CW, rapid scan, and pulsed EPR data acquisition is based on the Bruker Elexsys E540 spectrometer system.
