Mottness collapse without metallization in the domain wall of the triangular-lattice Mott insulator 1T-TaS_{2}

1T-TaS_{2} is a charge-density-wave (CDW) compound with a Mott-insulating ground state. The metallic state obtained by doping, substitution, or pulsed charge injection is characterized by an emergent CDW domain-wall network, while single domain walls can be found in the pristine Mott state. Here we study whether and how the single walls become metallic. Tunneling spectroscopy reveals partial suppression of the Mott gap and the presence of in-gap states strongly localized at the domain-wall sites. Using the real-space dynamical mean field theory description of the strongly correlated quantum-paramagnet ground state, we show that the local gap suppression follows from the increased hopping along the connected zigzag chain of lattice sites forming the domain wall. Furthermore, we show that full metallization is preempted by the splitting of the quasiparticle band into bonding and antibonding subbands due to the structural dimerization of the wall, explaining the presence of the in-gap states and the low density of states at the Fermi level.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:122

Enthalten in:

Physical review letters - 122(2019), 3 vom: 25. Jan., Seite 036802

Sprache:

Englisch

Beteiligte Personen:

Skolimowski, Jan [VerfasserIn]
Gerasimenko, Yaroslav [VerfasserIn]
Žitko, Rok [VerfasserIn]

Links:

Volltext

Themen:

Journal Article

Anmerkungen:

Date Completed 12.02.2019

Date Revised 15.02.2019

published: Print

Citation Status PubMed-not-MEDLINE

doi:

10.1103/PhysRevLett.122.036802

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM293613583