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arXiv · 2512.20611

Single-LED-pumped, room-temperature, solid-state maser

Michael Newns·Shirley Xu·Mingyang Liu·Zike Cheng·Yifan Yu·Ziqiu Huang·Max Attwood·Mark Oxborrow
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Abstract

Through their ability to achieve cryogenic levels of noise performance while operating at room temperature, optically-pumped, solid-state (OPSS) masers show great promise as quantum sensors, oscillators, and amplifiers. We here demonstrate maser oscillation in a microwave cavity containing a crystal of pentacene-doped para-terphenyl (ptc:ptp) pumped by a single, chip-scale LED. Here, unlike previous work, the size of the pump source does not dominate the size of the maser system as a whole. This miniaturization is achieved through invasive optical pumping in the form of a waveguide, the tip of which is embedded into the maser crystal. Using experimental measurements combined with microwave and optical simulations, we find that our approach offers at least a factor-of-2 enhancement in cooperativity over end-on optical excitation. We use our simulations to define a figure of merit for maser pumping efficiency, and conclude that there remains significant headroom to improve the performance of ptc:ptp masers through improved optical design.

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Michael Newns, Shirley Xu, Mingyang Liu, Zike Cheng, Yifan Yu, Ziqiu Huang, Max Attwood, Mark Oxborrow. 2026-01-07. Single-LED-pumped, room-temperature, solid-state maser. https://arxiv.org/abs/2512.20611

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