Bringing the NMR Paradigm to ESR

We describe a 94GHz pulsed Electron Spin Resonance (ESR) spectrometer capable of delivering arbitrary pulse sequences at kW power levels with sub-nanosecond timing resolution, where it is possible to detect coherent signals close to the thermal noise level within one nanosecond of the final pulse. Such a spectrometer represents a remarkable step forward, very significantly increasing excitation bandwidth and system deadtime compared to current state of the art. This level of performance has only become possible due to many technical advances in mm-wave technology (pulse generators, loads, isolators, switches, antennas), and these are outlined within the paper.