Quantum heat engines

• Applicants: Professor Dr. Joachim Ankerhold; Professor Dr. Fred Jendrzejewski; Professor Dr. Ferdinand Schmidt-Kaler
• Subject Area: Experimental Condensed Matter Physics ; Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2018 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 384846402

A fundamental understanding of the role of genuine quantum processes in quantum heat engines is currently lacking. While powerful theoretical tools exist to describe the operations of quantum heat engines in perturbative regimes, a consistent simulation platform for a non-perturbative approach needs yet to be formulated in order to capture non-adiabatic regimes, or very low temperatures and strong couplings, or quantum correlations between work agent and baths. On the experimental side, and based on the excellent progress for controlling single- and multi-particle systems, either with ultra-cold atoms or ion crystals or solid-state systems such as colour centres, we have seen first classical micro heat-engines that have been realised. However, heat engines operating deep in the quantum regime, or quantum refrigerators have only been proposed but not experimentally realised so far.Key to this project is exploring dedicated experimental quantum heat engines namely, single trapped ions or ion crystals, ultra-cold atoms or Nitrogen-Vacancy centres in diamonds. We thus aim at overcoming a significant boleneck in this research field. Common to these platforms is an excellent control of the relevant degrees of freedom such as interacting spins and motional quantum states. In close collaboration with theory we will identify and characterize quantumness in such heat engines. We will reveal the role of quantum fluctuations and investigate how they aect the operation of quantum heat engines, or how advanced multi-particle schemes may provide assets in the quantum regime. Building upon this, we aim for the identification of protocols in which an appropriate application of designed system-bath interactions allows for an enhancement of the power in quantum heat engines and quantum refrigerators.

• DFG Programme: Research Units
• Subproject of: FOR 2724: Thermal machines in the quantum world
• Major Instrumentation: Optical lattice set-up ; Pockels cell, diode laser, segmented ion trap
• Instrumentation Group: 5730 Spezielle Laser und -Stabilisierungsgeräte (Frequenz, Mode)