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arXiv · 2302.10811

Maser Threshold Characterization by Resonator Q-Factor Tuning

Christoph W. Zollitsch·Stefan Ruloff·Yan Fett·Haakon T. A. Wiedemann·Rudolf Richter·Jonathan D. Breeze·Christopher W. M. Kay
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Abstract

Whereas the laser is nowadays an ubiquitous technology, applications for its microwave analogue, the maser, remain highly specialized, despite the excellent low-noise microwave amplification properties. The widespread application of masers is typically limited by the need of cryogenic temperatures. The recent realization of a continuous-wave room-temperature maser, using NV$^-$ centers in diamond, is a first step towards establishing the maser as a potential platform for microwave research and development, yet its design is far from optimal. Here, we design and construct an optimized setup able to characterize the operating space of a maser using NV$^-$ centers. We focus on the interplay of two key parameters for emission of microwave photons: the quality factor of the microwave resonator and the degree of spin level-inversion. We characterize the performance of the maser as a function of these two parameters, identifying the parameter space of operation and highlighting the requirements for maximal continuous microwave emission.

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Christoph W. Zollitsch, Stefan Ruloff, Yan Fett, Haakon T. A. Wiedemann, Rudolf Richter, Jonathan D. Breeze, Christopher W. M. Kay. 2023-02-21. Maser Threshold Characterization by Resonator Q-Factor Tuning. https://doi.org/10.1038/s42005-023-01418-3

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