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An electron spin injection driven, paramagnetic solid-state MASER device

S. M. Watts·B. J. van Wees
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Abstract

In response to an external, microwave-frequency magnetic field, a paramagnetic medium will absorb energy from the field that drives the magnetization dynamics. Here we describe a new process by which an external spin injection source, when combined with the microwave field spin-pumping, can drive the paramagnetic medium from one that absorbs microwave energy to one that emits microwave energy. We derive a simple condition for the crossover from absorptive to emissive behavior. Based on this process, we propose a spin injection-driven paramagnetic MASER device.

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S. M. Watts, B. J. van Wees. 2006-08-04. An electron spin injection driven, paramagnetic solid-state MASER device. https://arxiv.org/abs/cond-mat/0608111

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