Ultra-low Noise, Room Temperature Maser Amplifiers

Room Temperature masers^[1], the microwave analogue of the laser, may enable near quantum limited room temperature amplification of microwave signals. However, deployment of room-temperature masers in practical applications will require eliminating the bulky and inefficient pump sources used in early embodiments. Recent developments have made significant progress in miniaturising the size and weight of these devices^[2], and improving their performance^[3], paving the way for their commercial application.

 

Towards more accurately quantifying the potential performance of molecular maser amplifiers, we here present for the first time the simple re-configuration of a molecular maser as a room temperature amplifier. We analyse the temporal response of the amplifier’s gain and noise temperature as well as it’s dynamic range and find it to compare favourably with current cryogenically cooled amplifiers. Additionally, we demonstrate maser oscillations and amplification using only a single, commercially available LED as the pump light source. This maser is the most compact yet reported and can operate in the strong coupling regime. Combined, our results demonstrate the practical promise of room temperature maser technology as a source of high-fidelity RF amplification.