Scientists in Finland have developed the world’s first cyclic heat engine that works inside a superconducting quantum circuit. The tiny device can use a small amount of heat from a quantum refrigerator and convert it into useful work. The breakthrough, achieved by researchers at Aalto University, could help make future quantum computers simpler, more affordable and easier to scale. In particular, it could reduce the huge number of microwave cables needed to connect thousands or even millions of quantum components. The challenge of building larger quantum computers Quantum computers use qubits , the basic units of quantum information. Unlike the bits in ordinary computers, qubits can exist in combinations of different states, allowing quantum computers to solve certain problems in ways that classical machines cannot. However, building a large quantum computer is extremely difficult. Finland’s Quantum Technology Strategy aims to develop a quantum computer with 1,000 logical qubits by 20...