Phys.org  December 16, 2022 Artificial quantum systems, based on superconducting circuits, can now amplify and detect even single microwave photons. However, this requires operating at millikelvin temperatures. Natural quantum systems can also be used for low-noise microwave amplification using stimulated emission effects; but they generate a higher noise, especially when operating above ~1 K. Researchers in Israel have demonstrated the use of electron spins in diamond as a quantum microwave amplifier operating with quantum-limited internal noise, even above liquid nitrogen temperatures. They reported on the amplifier’s design, gain, bandwidth, saturation power, and noise. According to the researchers this capability can […]