• Hofmann, Philip
• Balatsky, Alexander
• King, Phil D. C.
• Cacho, Cephise
• Ulstrup, Søren
• Miwa, Jill A.
• Jones, Alfred J. H.
• Rostami, Habib
• Bianchi, Marco
• Andreatta, Federico
• Biswas, Deepnarayan
• Čabo, Antonija Grubišić
• Sanders, Charlotte E.
• Chapman, Richard T.
• Springate, Emma

Abstract

<p>Using time- and angle-resolved photoemission spectroscopy, we study the response of metallic single-layer TaS2 in the 1H structural modification to the generation of excited carriers by a femtosecond laser pulse. A complex interplay of band structure modifications and electronic temperature increase is observed and analyzed by direct fits of model spectral functions to the two-dimensional (energy and k-dependent) photoemission data. Upon excitation, the partially occupied valence band is found to shift to higher binding energies by up to ≈100meV, accompanied by electronic temperatures exceeding 3000 K. These observations are explained by a combination of temperature-induced shifts of the chemical potential, as well as temperature-induced changes in static screening. Both contributions are evaluated in a semiempirical tight-binding model. The shift resulting from a change in the chemical potential is found to be dominant.</p>

Topics

• impedance spectroscopy
• two-dimensional
• band structure