Quantum Metrology Breakthrough at Caltech and JILA
Physicists at the California Institute of Technology have developed a new device that merges atomic clocks with quantum computers to help achieve ultraprecise time measurements, as reported in the journal Nature. Led by Professor of Physics Manuel Endres, the research team demonstrated how to perform quantum computations inside a tweezer clock array to reduce measurement errors. This advance aims to probe fundamental laws of nature, including Albert Einstein’s general theory of relativity, and assist in detecting dark matter and gravitational waves. The study was published alongside similar findings from a separate group at JILA in the journal Nature.
Integration of Tweezer Clocks and Quantum Computers
The Caltech device relies on tweezer clocks, which use arrays of neutral strontium atoms controlled individually by laser beams. While these clocks naturally track time with extreme accuracy, the new method introduces quantum entanglement directly into the array. Entanglement links particles together without direct contact, a mechanism required to reach the ultimate precision allowed by nature. Former Caltech postdoctoral scholar Ran Finkelstein and graduate students Richard Bing-Shiun Tsai and Xiangkai Sun served as lead authors on the study, titled “Universal quantum operations and ancilla-based readout for tweezer clocks.” Funding for the project came from agencies including the Army Research Office, the National Science Foundation, and the Defense Advanced Research Projects Agency.
Independent Advances in Precision Measurement
Parallel to the Caltech project, a separate research group led by Alec Cao at JILA achieved comparable results in quantum metrology, publishing their conclusions in the same issue of Nature. While Caltech focused on integrating quantum computing operations with tweezer clocks to manipulate strontium atoms, both studies highlight a broader movement toward utilizing entanglement for ultraprecise time measurement. These developments build upon existing facilities such as the Laser Interferometer Gravitational-wave Observatory, which is jointly managed by Caltech and MIT.
Funding and Institutional Support
The research at Caltech received extensive financial backing from multiple federal and academic bodies. Alongside the Army Research Office and the National Science Foundation’s Institute for Quantum Information and Matter, support was provided by the U.S. Department of Energy through its Quantum Systems Accelerator. Additional contributions came from Caltech’s Troesh Family Distinguished Scholars Program, the Taiwan-Caltech Scholarship, the Todd Alworth Larson Fellowship, the Council for Higher Education of Israel, and the Terman Faculty Fellowship at Stanford. The collaborative effort involved contributions from researchers now stationed at Tel Aviv University and Stanford University.
Frequently Asked Questions
What is a tweezer clock?
A tweezer clock is a precision timing device consisting of an array of neutral strontium atoms, where individual atoms are trapped and controlled by focused laser beams known as optical tweezers.
How does quantum entanglement improve atomic clocks?
Entanglement links particles together at a quantum scale, allowing researchers to coordinate the atoms and reduce measurement noise beyond the limits of unentangled systems.
What external institutions funded the Caltech research?
The project received support from the Army Research Office, the National Science Foundation, DARPA, the U.S. Department of Energy, and several academic fellowships.