Proceedings of the 10th Quantum Field Theory Under the Influence of External Conditions (QFEXT11); Editors: M. Asorey, M. Bordag, E. ElizaldeOpen Access

PHASE DIAGRAM FOR ASYMMETRIC PLANAR FERMIONIC SYSTEMS IN THE PRESENCE OF EXTERNAL FIELDS

RUDNEI O. RAMOS

Departamento de Física Teórica, Universidade do Estado do Rio de Janeiro, 20550-013 Rio de Janeiro, RJ, Brazil

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and

PATRÍCIA H. A. MANSO

Departamento de Física Teórica, Universidade do Estado do Rio de Janeiro, 20550-013 Rio de Janeiro, RJ, Brazil

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https://doi.org/10.1142/S2010194512007593Cited by:0 (Source: Crossref)

Abstract

The phase diagram of planar fermionic systems, with four-fermion interactions, are studied when external magnetic fields in different directions are applied to the system. The application of external fields can lead to an asymmetric system, which with the combined effects due to temperature and chemical potential, can lead to a rich phase diagram with multiple critical points. The phase transition we are primarily interested in studying is that of the metal-insulator type, in which our model is particularly well suitable. The relation between the phase transition with chiral symmetry breaking and the emergence of a gap (or the presence of a nonvanishing chiral vacuum expectation value) in the planar fermionic system, as a function of the different magnetic fields applied, is analyzed in details. The applications of our results in the context of condensed matter and quantum field theory at low dimensions are discussed.

Keywords:

PACS: 11.10.Kk, 71.30.+h, 11.30.Qc

References

K. S. Novoselovet al., Nature 438, 197 (2005). ADS, Google Scholar
D. Gross and A. Neveu, Phys. Rev. D 10, 3235 (1974). ADS, Google Scholar
K.G. Klimenko, Z. Phys. C54, 323 (1992); Theor. Math. Phys. 89, 1161 (1991); ibid. 90, 1 (1992) . Google Scholar
V. P. Gusynin, V. A. Miransky and I. A. Shovkovy, Phys. Rev. D 52, 4718 (1995); V. P. Gusynin, V. A. Miransky and I. A. Shovkovy, Nucl. Phys. B462, 249 (1996) . Google Scholar
H. Caldas and R. O. Ramos, Phys. Rev. B 80, 115428 (2009). ADS, Google Scholar
E. Abrahams, S. V. Kravchenko and M. P. Sarachik, Rev. Mod. Phys. 73, 251 (2001). ADS, Google Scholar
B. Rosenstein, B. Warr and S. H. Park, Phys. Rept. 205, 59 (1991). Google Scholar
C. Kittel, Introduction to Solid State Physics, 6th edn. (John Wiley & Sons, New York, 1986). Google Scholar
R. O. Ramos and P. H. A. Manso, Phase Transition in a Four-Fermi Type of Model in the Presence of an Oblique Magnetic Field, work in progress . Google Scholar
K. G. Klimenko, Z. Phys. C37, 457 (1988); B. Rosenstein, S. H. Park and B. J. Warr, Phys. Rev. D39, 3088 (1989); Phys. Rev. Lett. 62, 1433 (1989) . Google Scholar