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تسجيل مستخدم جديدA multi-frequency high-field pulsed EPR / ENDOR spectrometer
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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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We present pulsed electron-nuclear double resonance (ENDOR) experiments which enable us to characterize the coupling between bismuth donor spin qubits in Si and the surrounding spin bath of 29Si impurities which provides the dominant decoherence mech
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