Abstract
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.
Original language | English |
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Article number | 165421 |
Number of pages | 9 |
Journal | Physical Review B |
Volume | 99 |
Issue number | 16 |
DOIs | |
Publication status | Published - 15 Apr 2019 |
Externally published | Yes |