Sublimate Non-Linear Environments By Shaking Them

Floquet's method for controlling nonlinearities in a large class of physical systems. A publication by Nathan Goldman and Lucila Peralta Gavensky, Faculty of Sciences, in the journal PRX Quantum.

Nature dictates how particles interact with each other. In a metal, for example, electrons repel each other via Coulomb's law, as applied to two charges of opposite sign. However, in certain particular situations, the nature of the interactions can be modified: in certain materials, electrons actually attract each other and form Cooper pairs, giving rise to the phenomenon of superconductivity. Similarly, in optics, effective interactions between photons can be generated by the medium in which the light propagates. These “optical nonlinearities” are at the origin of many technologies that have revolutionized optical devices. In general, modifying interactions between particles and controlling nonlinearities can generate new phases of matter and lead to concrete technological applications.

In a new article published in the journal PRX Quantum , Nathan Goldman, Lucila Peralta Gavensky - Faculty of Science - and their colleagues introduce a new theoretical framework allowing the modification and control of nonlinearities in a broad class of systems physics, particularly in optics and quantum gases.

Their approach is based on the Floquet method, a strategy developed in atomic physics and solid state physics, which consists of subjecting a system to periodic temporal modulation (a jolt) in order to modify its properties in a controlled manner. By exploiting a theoretical approach based on quantum physics, the authors demonstrate that a well-chosen sequence of pulses can generate new interaction processes between particles, giving rise to highly controllable exotic nonlinearities. The authors apply this strategy to defined lattice systems, and they demonstrate that these unusual interaction processes make it possible to stabilize new ordered phases of matter.

The general approach introduced in this work paves the way for the engineering of unconventional optical nonlinearities in photonics and the manipulation of exotic interactions within quantum matter.