Collective lattice dynamics determine essential aspects of condensed matter, such as elastic and thermal properties. These exhibit strong dependence on the length-scale, reflecting the marked wavevector dependence of lattice excitations. The extreme ultraviolet transient grating (EUV TG) approach has demonstrated the potential of accessing a wavevector range corresponding to the 10s of nm length-scale, representing a spatial scale of the highest relevance for fundamental physics and forefront technology, previously inaccessible by optical TG and other inelastic scattering methods. In this manuscript we report on the capabilities of this technique in the context of probing thermoelastic properties of matter, both in the bulk and at the surface, as well as discussing future developments and practical considerations.
Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Maznev, Occhialini, Li, Comin, Nelson report financial support was provided by US Department of Energy. Caporaletti reports financial support was provided by Dutch Research Council. Monaco reports financial support was provided by Foundation of the Savings Bank of Padua and Rovigo.
(© 2023 The Authors.)