Undersökning av kvantfördelar i termodynamik med supraledande kretsar

Forskningsprojekt, 2022 – 2025

The technology advances of the last decades are forcing us to re-think the concepts of thermodynamics. An intense theoretical effort is underway to understand the role of quantum mechanical ingredients in thermodynamic processes.
However, experimental progress is hindered by a lack of comprehensive experimental platforms for quantum thermal machines. Here I aim to undertake an ambitious experimental search for quantum advantages in thermodynamics, based on a circuit quantum electrodynamics (QED) architecture. First, I will demonstrate the use of propagating microwave modes in waveguides as heat baths. In this arrangement, the heat exchanged by the baths can be measured with great accuracy and deep in the quantum regime. Then I will implement two types of novel quantum refrigerators. The refrigerators comprise small ensembles of superconducting quantum bits (from 2 up to 6) and are coupled to a hot and a cold heat bath. Each refrigerator is designed to pinpoint a specific quantum resource, either quantum coherence, or collective effects. I will measure the cooling power of the refrigerators while in situ exploring an unprecedently large space of parameters. I expect two scientific breakthroughs: the observation of unambiguously nonclassical features in thermodynamic observables and the determination of advantages enjoyed by quantum thermal machines. This work will deepen our understanding of quantum thermodynamics while establishing a new standard for experiments in the field.