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arXiv · 0803.3054

A multi-frequency high-field pulsed EPR / ENDOR spectrometer

Gavin W. Morley·Louis-Claude Brunel·Johan van Tol
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Abstract

We describe a pulsed multi-frequency electron paramagnetic resonance spectrometer operating at several frequencies in the range of 110-336 GHz. The microwave source at all frequencies consists of a multiplier chain starting from a solid state synthesizer in the 12-15 GHz range. A fast PIN-switch at the base frequency creates the pulses. At all frequencies a Fabry-Perot resonator is employed and the pi/2 pulse length ranges from ~100 ns at 110 GHz to ~600 ns at 334 GHz. Measurements of a single crystal containing dilute Mn2+ impurities at 12 T illustrate the effects of large electron spin polarizations. The capabilities also allow for pulsed electron nuclear double resonance experiments as demonstrated by Mims ENDOR of 39K nuclei in Cr:K3NbO8.

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Gavin W. Morley, Louis-Claude Brunel, Johan van Tol. 2008-03-20. A multi-frequency high-field pulsed EPR / ENDOR spectrometer. https://doi.org/10.1063/1.2937630

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