Nonthermal pathways to ultrafast control in quantum materials
By Simon Gerber, PSI
Based on article published in Reviews of Modern Physics
An international team with participation of the Paul Scherrer Institute (PSI) reviews how light can fundamentally change the properties of solids and how these effects can be used for future applications. The team summarises the progress in this field, which is based among other techniques on experiments that can also be carried out at the Swiss X-ray free-electron laser SwissFEL, in the journal Reviews of Modern Physics.
Simon Gerber from PSI and his colleagues review the recent progress in utilizing ultrafast light-matter interaction to control the macroscopic properties of quantum materials.
An emphasis is placed on photoinduced phenomena that do not result from ultrafast heating effects but rather emerge from microscopic processes that are inherently nonthermal in nature. On the one hand, many of these processes can be described as transient modifications to the free energy landscape resulting from the redistribution of quasiparticle populations, the dynamical modification of coupling strengths, and the resonant driving of the crystal lattice. On the other hand, different pathways result from the coherent dressing of a material’s quantum states by the light field. The team reviews a selection of recently discovered effects leveraging these mechanisms, including the technological advances that led to their discovery, and presents a road map for how the field can harness these nonthermal pathways to create new functionalities.