Scientists boost quantum signals while reducing noise

MIT News  February 9, 2023 Squeezing of the electromagnetic vacuum is an essential metrological technique used to reduce quantum noise in applications spanning gravitational wave detection, biological microscopy and quantum information science. In superconducting circuits, the resonator-based Josephson-junction parametric amplifiers conventionally used to generate squeezed microwaves are constrained by a narrow bandwidth and low dynamic range. An international team of researchers (USA – MIT, MIT Lincoln Laboratory, industry, Australia) developed a dual-pump, broadband Josephson travelling-wave parametric amplifier that combined a phase-sensitive extinction ratio of 56 dB with single-mode squeezing on par with the best resonator-based squeezers. They demonstrated two-mode squeezing at […]

Honing quantum sensing

MIT News  September 25, 2018 Extreme sensitivity of quantum sensors to their surrounding environment creates the vexing problem of environmental noise in quantum sensor systems. A team of researchers in the US (MIT, Yale University) has developed an approach that is complementary to existing Dynamical decoupling and established error-corrected quantum sensing (ECQS) methods. This approach allows frequency-independent filtering, because it exploits spatial rather than temporal noise correlations. The new ECQS scheme makes use of noise correlations at different positions in a quantum sensor. In this way, the new approach can tell signal from noise even in the common case where […]