Researchers from the National Institute for Quantum Science and Technology (NQSTI), in collaboration with the University of Florence, the National Institute of Optical Research (CNR-INO), the LENS Institute and INFN, have developed an instrument that allows the simultaneous observation of classical and quantum phenomena. In this study, published in Optica , they use optically levitated glass nanospheres to investigate the boundary between these realms.

The instrument was developed as a joint effort of the European Laboratory for Nonlinear Spectroscopy (LENS), the Florence branch of the National Institute for Nuclear Physics (INFN), the Department of Physics and Astronomy of the University of Florence, the National Research Council’s National Institute of Optical Research (CNR-INO) and NQSTI.
Quantum mechanics describes the behavior of matter on a microscopic scale, where physical properties deviate significantly from those of macroscopic classical systems. Traditionally, classical and quantum behavior have been studied separately, but a device developed by CNR-INO researchers makes it possible to experimentally investigate both behaviors in a single system.
The system makes use of optical levitation, a phenomenon in which a tightly focused laser beam traps nano-objects in free space. The effect was first observed in the 1980s and further refined by Arthur Ashkin, who won the 2018 Nobel Prize in Physics for his contributions to optical trapping.
An Italian research team led by Francesco Marin of the University of Florence and CNR-INO has introduced a technique to simultaneously trap two nano-glass spheres using laser light of different wavelengths. The trapped particles oscillate in an optical potential at well-defined frequencies, allowing the direct observation of both classical and quantum behavior.
These nano-oscillators are one of the rare systems that allow studying the behavior of macroscopic objects in a precisely controlled way: the spheres are charged and interact with each other, so that the trajectory that one sphere follows is highly dependent on the trajectory of the other. This paves the way for the study of collectively interacting nanosystems in both the classical and quantum realms, allowing experimental exploration of the delicate boundary between these two worlds .
Francesco Marin, University of Florence
sauce:
National Institute of Optics (CNR-INO)