Amplifying microwave pulses with a single qubit engine fueled by quantum measurements

Recent progress in manipulating individual quantum systems enables the exploration of engines exploiting nonclassical resources. One of the most appealing is the energy provided by the inherent backaction of quantum measurements. While a handful of experiments have investigated the inner dynamics of engines fueled by measurement backaction, powering a task by such an engine is missing. Here, we demonstrate the amplification of microwave signals by an engine fueled by repeated quantum measurements of a superconducting transmon qubit. Using feedback, the engine acts as a quantum Maxwell demon operating without a hot thermal source. Measuring the gain of this amplification constitutes a direct probing of the work…

• SV
  Silicon Valley Community Foundation
• JT
  John Templeton Foundation

  Award: 61835
• FQ
  Foundational Questions Institute

  Award: FQXi-IAF19-05
• NR
  National Research Foundation Singapore
• AN
  Agence Nationale de la Recherche

  Award: ANR-PRC-CES47
• CF
  Centre for Quantum Technologies

  Award: S24Q2d0009