At room temperature, titanium diselenide is a metallic crystal with pronounced electron-electron as well as electron-phonon correlations. At low temperature, a metal-insulator phase transition occurs concurrently with the formation of a charge density wave and a periodic lattice distortion. In collaboration with the research group Dynamics of Correlated Materials, we investigated the response of the electronic structure of this material to infrared and infrared optical excitation. The transient electronic structure was measured with time-, energy- and momentum-resolution by time- and angle-resolved photoelectron spectroscopy (trARPES) employing femtosecond extreme-ultraviolet laser pulses.

full publication: Monney et al., Phys. Rev. 94, 165165 (2016).