Benchmarking Organic Gain Media for Milliwatt L-Band Room-Temperature Solid-State Masers

Molecular room-temperature masers have emerged as promising sources of coherent microwaves, but systematic comparisons of available organic gain media under uniform conditions have remained elusive. This paper presents a comprehensive characterisation of two organic gain media, pentacene and 6,13 diazapentacene, each doped into para-terphenyl at two distinct concentrations. This work evaluates reported L-band masing samples under identical conditions, providing insights into optimal concentrations and gain media for specific applications. An optimised system produced a milestone peak power of 2.34 mW (+3.69 dBm) with spectral coherence times of 465 ns and coherence lengths reaching 150 m, marking the first achievement of whole-milliwatt output and demonstrating significant potential for high-power applications. Coupling to a high-Q (quality factor) cavity enables collective spin-photon interactions within the strong-coupling regime, consistent with cavity quantum electrodynamics (cQED) analysis. Finally, the feasibility of applying these coherent masers to advanced technologies such as radar, secure communications, and qubit interfaces is assessed quantitatively, bridging the gap between fundamental maser physics and real-world deployment.