The Future of Quantum Computing

The Physics That Curves a Ping-Pong Ball Just Showed Up in Quantum Light

Physics The Physics That Curves a Ping-Pong Ball Just Showed Up in Quantum LightBy Benjamin A. Senn, Paul Scherrer InstituteSeptember 15, 20264 Mins Read Facebook Twitter Pinterest Telegram LinkedIn WhatsApp Email Reddit Share Facebook Twitter LinkedIn Pinterest Telegram Email Reddit Putting spin on a ping-pong ball changes its trajectory – a similar effect also occurs in the quantum world. Credit: AI-generated symbolic imageResearchers have directly observed the optical Magnus effect for the first time, revealing a tiny shift in laser interactions that could affect the precise control of qubits in quantum computers.Anyone who has watched a spinning soccer ball curve around a defensive wall has seen what happens when spin changes an object’s path through the air. The ball bends away from the direction it initially seemed to be traveling because its rotation creates an uneven force as it moves.Physicists call this the Magnus effect. Researchers have now observed an optical counterpart of the same phenomenon at a vastly smaller scale, using laser light and a single trapped calcium ion.Instead of making the ion curve through space, the optical effect shifts the point where a tightly focused laser interacts most strongly with it. An international team led by scientists at the Paul Scherrer Institute PSI measured this tiny sideways displacement experimentally for the first time.The finding could matter for quantum computers that use lasers to control individual qubits with extreme precision. If the shift is overlooked, the laser may not act exactly where researchers expect. But the effect could also become useful.“The forces it generates could be used to couple qubits to one another, enabling more complex computations,” explains first author Philip Leindecker from the PSI Center for Photon Science and the Department of Physics at ETH Zurich.The laser misses its expected targetAt first glance, the strongest interaction should occur at the center of the laser beam, where t