Title : |
Preformed excitonic liquid and charge density wave in transition metal dichalcogenides |
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Speaker | : | Arghya Taraphder, Physics & Meteorology, IIT Kharagpur |
Date | : | May 15, 2013 |
Abstract | : |
Recent experiments on transition metal dichalcogenides contradict the old view of the charge density wave arising from nested bands. An intrinsically strong coupling view, involving a charge density wave state arising as a Bose condensation of preformed excitons emerges as an attractive, albeit rarely discussed alternative. We revisit some of these systems in this context [1]. Using local density approximation plus multi-orbital dynamical mean field theory, we show that this preformed excitonic scenario shows very good agreement with a wide variety of normal state data. We argue that the charge density wave and superconducting states in a set of transition metal dichalcogenides should generically be viewed as instabilities of such a correlated, preformed quantum liquid. [1] A. Taraphder, et al., Phys. Rev. Lett. 101, 136401 (2008); ibid 106, 236405 (2011); arXiv:1212.1026; AIP Conf. Proc. 1461, 170 (2012). |