Scientists at the University of Warsaw have made significant strides in quantum mechanics by creating anti-clockwise twists in light through the superposition of two clockwise-twisted beams. This research, published in the journal Optica, demonstrates the potential for observing two-dimensional quantum backflow, a phenomenon where quantum particles can move in counterintuitive directions, contrary to classical mechanics. The team, led by Dr. Radek Lapkiewicz, manipulated light to give rise to locally positive orbital angular momentum (OAM) in dark regions of the resulting superposition, defined as azimuthal backflow.
This breakthrough is essential for enhancing optical technologies, such as microscopy, precision timekeeping, and optical trapping. Unlike classical objects, quantum particles can exist in superpositions, allowing for unexpected behaviors such as backflow. Past studies and theoretical work by notable physicists, including Yakir Aharonov and Michael Berry, laid the groundwork for this finding. The researchers utilized a Shack-Hartman wavefront sensor for their measurements, revealing new implications for light-matter interactions. Ultimately, this work represents a critical step toward the experimental observation of quantum backflow in two dimensions, potentially influencing advancements in various scientific applications.
