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

TL;DR

This paper demonstrates a room-temperature quasi-continuous-wave pentacene maser operating at 1.45 GHz, powered by a Ce:YAG luminescent concentrator, showing potential for practical microwave amplification without cryogenic cooling.

Contribution

It introduces a novel room-temperature CW pentacene maser setup using a Ce:YAG luminescent concentrator and specific resonator design, enabling practical microwave amplification.

Findings

Operates at 1.45 GHz with ~4 ms duration

Achieves output power up to -25 dBm

Feasible CW operation at room temperature with proper heating management

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$4 ms and an output power of up to -25 dBm. The maser is optically pumped by a cerium-doped YAG (Ce:YAG) luminescent concentrator (LC) whose wedge-shaped output is embedded inside a 0.1% pentacene-doped para-terphenyl (Pc:Ptp) crystal. The pumped crystal is located inside a ring of strontium titanate (STO) that supports a TE$_{01\delta}$ 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.