A diamond-based quantum amplifier

https://phys.org/news/2022-12-diamond-based-quantum-amplifier.html

"electron spins in diamond quantum microwave amplifier... quantum-limited internal noise above liquid nitrogen temperatures... boost sensitivity compared to non-masing devices... voltage gain bandwidth product of the maser, expected saturation power, and noise temperature... cryogenic, low-noise microwave amplification... quantum-limited amplification performance... multiple echoes and super-radiance; features of significance mainly for research in cavity quantum electrodynamics"

Related: Quantum electrodynamics verified with exotic atoms

https://phys.org/news/2023-05-quantum-electrodynamics-exotic-atoms.html