Abstract: Owing to their wave-like nature, quantum systems can never be truly at rest. Indeed, the value of some observables—those which do not commute with the Hamiltonian—fluctuate, even when the system is in its ground state. Following major advances in the manipulation and control of quantum systems, the prospect of extracting useful work out of these ubiquitous fluctuations becomes increasingly tangible.
“In this talk, I will present a new design for a quantum engine where local measurements on a many-body system are used to extract work from the ground state fluctuations of local observables. Indeed, performing local energy measurements on a system whose ground state is entangled can reveal excited states from which work can be extracted via local feedback operations. The engine is powered by the energy gap between the local ground state and the entangled many-body ground state. This quantum resource is essentially “free” in the setup at stake as it can simply be generated by coupling the interacting many-body system to a cold reservoir.
I will illustrate this proposal with two different systems: a chain of coupled qubits and a network of coupled harmonic oscillators. These models respectively correspond to fermionic and bosonic excitations.”
Watch Etienne Jussiau’s talk here: https://youtu.be/Jaw5GtuyLFQ