Excitation spectrum of TTF-TCNQ: a finite temperature calculation

Central European Journal of Physics - Tập 11 - Trang 111-118 - 2012
Željana Bonačić Lošić1
1Faculty of Science, University of Split, Split, Croatia

Tóm tắt

In this paper we study the excitation spectrum of the organic conductor tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) using finite temperature calculations. The effect of electronelectron interaction is considered within the random phase approximation (RPA). Our results show the temperature dependent plasmon and dipolar mode corresponding qualitatively to the modes obtained previously using zero temperature formalism assigned to the observed excitations at 10 meV and 0.75 eV. These modes have an essential influence on the energy-loss function. The obtained results are in good qualitative agreement with the optical and EELS data of TTF-TCNQ.

Tài liệu tham khảo

J.J. Ritsko et al., Phys. Rev. Lett. 34, 1330 (1975) D.B. Tanner et al., Phys. Rev. B 13, 3381 (1976) C.S. Jacobsen, In: S. Barišić et al. (Ed.) Lecture Notes in Physics, (Springer-Verlag 1979), 95, 223 H. Basista et al., Phys. Rev. B 42, 4088 (1990) P. Županović, A. Bjeliš, S. Barišić, Z. Phys. B 101, 387 (1996) P. Županović, A. Bjeliš, S. Barišić, Europhys. Lett. 45, 188 (1999) Ž. Bonačić Lošić, P. Županović, Cent. Eur. J. Phys. 8, 283 (2010) Ž. Bonačić Lošić, Cent. Eur. J. Phys. 10, 172 (2012) P.F. Williams, A.N. Bloch, Phys. Rev. Lett. 36, 64 (1976) L.M. Khan, J. Ruvalds, Phys. Rev. B 17, 4600 (1978) D. Pines, P. Nozières, The Theory of Quantum Liquids (W. A. Benjamin, Inc., New York, 1966) G.D. Mahan, Many-Particle Physics (Plenum, New York, 1981) B. Wunsch et al., New J. Phys. 8, 318 (2006) E.H. Hwang, S. Das Sarma, Phys. Rev. B 75, 205418 (2007) M. Polini et al., Phys. Rev. B 77, 081411(R) (2008) P.K. Pyatkovskiy, J. Phys.: Condens. Matter 21, 025506 (2009) E.H. Hwang, S. Das Sarma, Phys. Rev. B 80, 205405 (2009) LI Zhao-Zhe, Commun. Theor. Phys. (Beijing, China) 52, 361 (2009) T. Vazifehshenas et al., Phys. Lett. A 374, 4849 (2010) D.V. Tuan, N.Q. Khanh, Proc. Natl. Conf. Theor. Phys. 35, 12 (2010) D.V. Tuan, N.Q. Khanh, arXiv:cond-mat/1101.2884 P.F. Williams, A.N. Bloch, Phys. Rev. B 10, 1097 (1974) D. Jérome, H.J. Schulz, Adv. Phys. 31, 299 (1982) A.L. Fetter, J.D. Walecka, Quantum Theory of Many-Particle Systems (W.A. Benjamin, Inc., New York, Amsterdam, 1964) A.S. Pennelly, C.J. Echardt, Chem. Phys. 12, 89 (1976) D. Pines, Elementary Excitations in Solids (McGraw-Hill Book Company, New York, 1971) J. Fink et al., J. Electron Spectrosc. Relat. Phenom. 117, 287 (2001) R.F. Egerton, Rep. Prog. Phys. 72, 016502 (2009)