On January 14, 2025, physicists from the Massachusetts Institute of Technology (MIT) made a groundbreaking discovery by measuring the quantum geometry of electrons in solids.
While researchers have long been able to gauge the energies and velocities of electrons in crystalline materials, the geometric aspects of these quantum systems had previously been theoretical or even unmeasurable. This new work, published in Nature Physics, is poised to enhance our understanding and manipulation of quantum properties in materials, according to Riccardo Comin, an associate professor at MIT and leader of the study.
Comin stated, "We have developed a plan to obtain completely new information that was not accessible before." The implications of this research extend beyond the specific materials studied, as noted by Mingu Kang, the lead author and now a postdoctoral fellow at Cornell University.
In quantum physics, electrons can be represented as points in space or as wave-like forms. The core of this research revolves around the wave function, which can be visualized as a surface in three-dimensional space. The study distinguishes between simple wave functions, akin to a sphere, and complex ones, reminiscent of a Möbius strip.
The ability to measure the quantum geometry of wave functions is increasingly critical as more quantum materials are discovered, which hold potential applications in quantum computing and advanced electronic devices. The MIT team utilized angular-resolved photoemission spectroscopy (ARPES) to tackle this challenge, building on their previous work that revealed the unique properties of a quantum material known as kagome metal.
Kang emphasized that this new capability is the result of close collaboration between theorists and experimentalists, marking a significant step forward in quantum research.