Scientists have created the first quantum battery integrated into a quantum computer using superconducting qubits. This experiment demonstrates faster charging through quantum interactions compared to classical methods. The development could pave the way for more efficient quantum technologies.
In a pioneering experiment, researchers at Hefei National Laboratory in China have constructed a quantum battery within a quantum computer, marking a significant step toward understanding energy storage in quantum systems. The battery utilizes 12 qubits made from tiny superconducting circuits, each controlled via microwaves. These qubits serve as individual battery cells and interact with their nearest neighbors, allowing the team to test different charging approaches.
Dian Tan, lead researcher at the lab, emphasized the need for quantum energy solutions: “Many future quantum technologies will need their quantum versions of batteries.” The team compared a classical charging protocol, which avoids quantum interactions, against one that leverages them. The quantum method delivered higher average power more rapidly, achieving up to twice the maximum power of the classical approach.
Alan Santos from the Spanish National Research Council highlighted the practicality: “The quantum battery achieves maximum power that is up to twice as large as the classical charging power.” This efficiency holds even with qubits limited to nearest-neighbor interactions, a common setup in superconducting quantum computers.
Experts offered mixed views on the implications. James Quach at Australia's Commonwealth Scientific and Industrial Research Organisation noted that prior theories suggested quantum batteries could enhance quantum computer efficiency and scalability: “This was a theoretical idea that we proposed only recently, but the new work could really be used as the basis to power future quantum computers.”
However, Dominik Šafránek at Charles University in the Czech Republic cautioned that direct comparisons remain challenging, with no clear path to practical devices yet. Kavan Modi from the Singapore University of Technology and Design added that advantages might be modest and offset by issues like noise or slow controls in real quantum systems. Despite these hurdles, Tan sees promise in using such batteries for quantum computers and plans to integrate them with a qubit-based quantum heat engine for energy production and storage.
This work, published in Physical Review Letters, underscores the growing focus on energy management as quantum technologies advance, potentially addressing the high energy demands of large-scale quantum computers.