Aalto University researchers built the first cyclic quantum heat engine in a superconducting circuit, using a qubit to turn heat into useful work near absolute zero.
Single-shot measurements across up to three cycles showed the device produced positive work, with power and efficiency matching simulations rather than merely shuttling heat around the circuit.
One tunable quantum circuit refrigerator both heated and cooled a flux-tunable transmon qubit, letting the team complete a four-stage quantum Otto cycle inside cryogenic hardware already used for quantum computing.
Superconducting circuits had not previously demonstrated a cyclic quantum heat engine, even though they are a leading platform for quantum computing, communication and sensing.
The result points to more autonomous cryogenic control in larger quantum computers, potentially cutting the millions of microwave cables that Aalto says a 1,000-logical-qubit system by 2035 could otherwise require.
By solving the wiring crisis, have scientists accidentally created a new thermal noise problem inside quantum computers?
Could a sand-sized engine sever the quantum industry’s reliance on a rare gas sourced from nuclear stockpiles?
World's First Cyclic Superconducting Quantum Heat Engine: Breakthrough Paves Way for Scalable Quantum Computing
Overview
On July 13, 2026, researchers unveiled the world's first cyclic superconducting quantum heat engine, marking a major milestone in quantum technology. This engine is the first to operate experimentally within superconducting circuits and features a simple, versatile design that uses a single, controllable quantum refrigerator as both its hot and cold environment. This streamlined approach makes the engine more adaptable for various applications and confirms the practical feasibility of quantum heat engines. By fusing quantum physics and thermodynamics, this breakthrough opens new possibilities for future technologies and advances the field of quantum computing.