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arXiv · 2008.07627

Room-temperature quasi-continuous-wave pentacene maser pumped by an invasive Ce:YAG luminescent concentrator

Hao Wu·Xiangyu Xie·Wern Ng·Seif Mehanna·Yingxu Li·Max Attwood·Mark Oxborrow
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Abstract

We present in this work a quasi-continuous-wave (CW) pentacene maser operating at 1.45 GHz in the Earth's magnetic field at room temperature with a duration of $\sim$4 ms and an output power of up to -25 dBm. The maser is optically pumped by a cerium-doped YAG (Ce:YAG) luminescent concentrator (LC) whose wedge-shaped output is embedded inside a 0.1% pentacene-doped para-terphenyl (Pc:Ptp) crystal. The pumped crystal is located inside a ring of strontium titanate (STO) that supports a TE$_{01δ}$ mode of high magnetic Purcell factor. Combined with simulations, our results indicate that CW operation of pentacene masers at room-temperature is perfectly feasible so long as excessive heating of the crystal is avoided.

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Hao Wu, Xiangyu Xie, Wern Ng, Seif Mehanna, Yingxu Li, Max Attwood, Mark Oxborrow. 2020-12-01. Room-temperature quasi-continuous-wave pentacene maser pumped by an invasive Ce:YAG luminescent concentrator. https://doi.org/10.1103/physrevapplied.14.064017

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