A group of researchers from INFN, a European nonlinear spectroscopy laboratory, Sezione, Firenze and Firenze University demonstrated a "vector" polaron by suspending nanospheres in an optical cavity. In a paper published in the journal Nature Physics, the team described their work and the possible uses of their results. Tania Monteiro of University College London published a news and opinion (news &; Views) summarizes the preliminary work of quantum control by using polarizable nanoparticles and the new work of the team in this regard.
As Monteiro pointed out, strong coupling is an unusual mixed state of light interaction. In this state, the interaction between light and light cannot be described only by the composition of matter and light. She also pointed out that polaron is a mixed state produced by the interaction between light and matter, which exists everywhere. She explained that in this new study, the "vector" polaron (that is, condensed quasi-particles) is produced by nanospheres suspended in an optical cavity, which will cause light to hybridize with motion on a plane rather than an axis.
In their work, the team adopted the coherent scattering method, that is, first captured the nanospheres with tweezers in vacuum. Then, the team used the potential of tweezers to create the X axis and the Y axis, which led to the development of a plane perpendicular to the incident laser used to create tweezers. The cavity is then filled with scattered tweezer photons. In this structure, the cavity field is strongly coupled with the motion of X axis and Y axis, but strongly coupled with the motion of X axis. Mirrors are used to promote higher-level quantum cooperation, which makes the system a quantum coherent system. In this system, the rate of information exchange begins to exceed the lifetime of quantum coherence. The results prove the existence of vector polaron.
This demonstration may pave the way for a new method of quantum information transmission, and it also marks a step to create optical mechanical entanglement at room temperature.