Light-control of materials via nonlinear phononics

Nonlinear phononics is the phenomenon in which a coherent dynamics material along set of phonons launched after its infrared-active are selectively excited using external light pulses. The microscopic mechanism underlying this nonlinear coupling pumped mode to other phonon modes present material. couplings can cause finite time-averaged atomic displacements with or without broken crystal symmetries depending on order, magnitude and sign nonlinearities. Such lattice coordinates be used control physical properties materials even induce transient phases lower symmetries. Light-control via has become practical reality due availability intense mid-infrared lasers that drive large-amplitude oscillations materials. Mid-infrared pump induced insulator–metal transitions spin orbital order melting have been observed pump–probe experiments. First principles based theory developed, it better understand how evolves excitation phonons. This predict light-induced switching ferroelectric polarization as well ferroelectricity paraelectrics ferromagnetism antiferromagnets, partially confirmed recent review summarizes experimental theoretical developments within emerging field.