2009/11/18 by Jasper van Wezel, Paul Nahai-Williamson, S. S. Saxena +1 · 2 citations
Engineering · Materials Science · Physics and Astronomy · #2D Materials and Applications #Angle-resolved photoemission spectroscopy #Charge density wave #Condensed matter physics #Electronic structure #Exciton #Organic and Molecular Conductors Research #Perovskite Materials and Applications #Phonon #Physics #Superconductivity #cond-mat.str-el
paper · pdf · doi:10.1209/0295-5075/89/47004
published as Europhysics Letters, 89, 47004 (2010) · 4 pages, 2 figures
arxiv created 2009/11/18 · openalex publication_date 2010/02/01 · arxiv updated 2010/04/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Recently there has been a renewed interest in the charge density wave transition of TiSe 2 , fuelled by the possibility that this transition may be driven by the formation of an excitonic insulator or even an excitonic condensate. We show here that the recent ARPES measurements on TiSe 2 can also be interpreted in terms of an alternative scenario, in which the transition is due to a combination of Jahn-Teller effects and exciton formation. The hybrid exciton-phonons which cause the CDW formation interpolate between a purely structural and a purely electronic type of transition. Above the transition temperature, the electron-phonon coupling becomes ineffective but a finite mean-field density of excitons remains and gives rise to the observed diffuse ARPES signals.