Aalto University researchers build first superconducting quantum heat engine

Researchers at Aalto University have developed the world’s first cyclic quantum heat engine built within a superconducting circuit. Led by Academy Professor Mikko Möttönen, the study demonstrates how microscopic heat in ultracold environments can be utilized to repeatedly produce positive work.

The device operates by reproducing a thermodynamic Otto cycle inside a superconducting chip located in a cryostat near absolute zero. The engine consists of three primary microscopic components: a transmon qubit acting as the working medium, a resonator to monitor energy states, and a specialized quantum-circuit refrigerator that serves as both the hot and cold environments.

This experiment, conducted using Finland’s national research infrastructure OtaNano, merges classical thermodynamics with quantum mechanics. The proof of concept provides insights into how thermodynamic processes behave when influenced by quantum effects like entanglement and superposition, potentially advancing the development of quantum computers with significantly larger numbers of qubits.