Delicate competition between different excitonic orderings in Ta$_2$NiSe$_5$

Chatterjee, Banhi (author), Golež, Denis (author), Mravlje, Jernej (author)

We investigate the energetics of the quasi-one-dimensional layered compound Ta$_2$NiSe$_5$ in the excitonic phase within the six-band model using Hartree–Fock calculations. We calculate energies of states with different kinds of excitonic order and show that they differ by less than meV and depend sensitively on precise values of interchain hopping matrix elements.

• Language: English
• Keywords: condensed matter physics, semiconductors, 2D materials, excitonic fluctuations, structural instabilities, electron correlations, DFT calculations, mean-field theory
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: 10 str.
• Numbering: Vol. 15, iss. 5, art. no. 414
• PID: 20.500.12556/RUL-177294
• UDC: 538.9
• ISSN on article: 2073-4352
• DOI: 10.3390/cryst15050414
• COBISS.SI-ID: 262345219
• Publication date in RUL: 19.12.2025

Record is a part of a journal

• Title: Crystals
• Shortened title: Crystals
• Publisher: MDPI
• ISSN: 2073-4352
• COBISS.SI-ID: 36677893

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: fizika kondenzirane snovi, polprevodniki, 2D materiali