Room-Temperature Silicon Carbide Maser: Unveiling Quantum Amplification and Cooling

We present the very first demonstration of a maser utilizing silicon vacancies (VSi) within 4H silicon carbide (SiC). Leveraging an innovative feedback-loop technique, we elevate the resonator's quality factor, enabling maser operation even above room temperature. The SiC maser's broad linewidth showcases its potential as an exceptional preamplifier, displaying measured gain surpassing 10dB and simulations indicating potential amplification exceeding 30dB. By exploiting the relatively small zero-field splitting (ZFS) of VSi in SiC, the amplifier can be switched into an optically-pumped microwave photon absorber, reducing the resonator's mode temperature by 35 K below operating conditions. This breakthrough holds promise for quantum computing advancements and fundamental studies in cavity quantum electrodynamics. Our findings highlight SiC's transformative potential in revolutionizing contemporary microwave technologies.