| Title: | Dissecting Mott and charge-density wave dynamics in the photoinduced phase of 1T-TaS[sub]2 |
|---|
| Authors: | ID Simoncig, Alberto (Author)
ID Stupar, Matija (Author)
ID Ressel, Barbara (Author)
ID Saha, Tanusree (Author)
ID Rebernik Ribič, Primož (Author)
ID De Ninno, Giovanni (Author) |
|---|
| Files: |
This document has no files that are freely available to the public. This document may have a physical copy in the library of the organization, check the status via COBISS.  |
|---|
| Language: | English |
|---|
| Work type: | Unknown |
|---|
| Typology: | 1.01 - Original Scientific Article |
|---|
| Organization: | UNG - University of Nova Gorica
|
|---|
| Abstract: | The two-dimensional transition-metal dichalcogenide 1T−TaS2 is a complex material standing out for its puzzling low temperature phase marked by signatures amenable to both Mott-insulating and charge-density wave states. Electronic Mott states, coupled to a lattice, respond to coherent optical excitations via a modulation of the lower (valence) Hubbard band. Such dynamics is driven by strong electron-phonon coupling and typically lasts for tens of picoseconds, mimicking coherent structural distortions. Instead, the response occurring at the much faster timescale, mainly dominated by electronic many-body effects, is still a matter of intense research. By performing time- and angle-resolved photoemission spectroscopy, we investigated the photoinduced phase of 1T−TaS2 and found out that its lower Hubbard band promptly reacts to coherent optical excitations by shifting its binding energy towards a slightly larger value. This process lasts for a time comparable to the optical pump pulse length, mirroring a transient change of the onsite Coulomb repulsion energy (U). Such an observation suggests that the correction to the bare value of U, ascribed to the phonon-mediated screening which slightly opposes the Hubbard repulsion, is lost within an interval of a few tens of femtoseconds and can be understood as a fingerprint of electronic states largely decoupled from the lattice. Additionally, these results enforce the hypothesis, envisaged in the current literature, that the transient photoinduced states belong to a sort of crossover phase instead of an equilibrium metallic one. |
|---|
| Keywords: | ultrafast phenomena, time resolved photoemission, strongly correlated systems, transition metal dichalcogenide |
|---|
| Year of publishing: | 2021 |
|---|
| Number of pages: | str. 1-7 |
|---|
| Numbering: | Vol. 103, iss. 5 |
|---|
| PID: | 20.500.12556/RUNG-6471 |
|---|
| COBISS.SI-ID: | 59328771 |
|---|
| UDC: | 53 |
|---|
| ISSN on article: | 2469-9950 |
|---|
| DOI: | 10.1103/PhysRevB.103.155120 |
|---|
| NUK URN: | URN:SI:UNG:REP:OCCSHWAX |
|---|
| Publication date in RUNG: | 13.04.2021 |
|---|
| Views: | 3384 |
|---|
| Downloads: | 0 |
|---|
| Metadata: |    |
|---|
|
:
|
Copy citation |
|---|
| | | | Average score: | (0 votes) |
|---|
| Your score: | Voting is allowed only for logged in users. |
|---|
| Share: |  |
|---|
Hover the mouse pointer over a document title to show the abstract or click
on the title to get all document metadata. |
