2022/10/16 by M. E. Carrington, Carrington, Margaret E., Wade N. Cowie +3
Chemistry · Physics and Astronomy · #Anisotropy #Chemistry #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Coupling (piping) #Dirac (video compression format) #Dirac fermion #FOS: Physical sciences #Fermion #Materials science #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Phase transition #Photon #Physics #Polarization (electrochemistry) #Quantum and electron transport phenomena #Quantum mechanics #Strongly Correlated Electrons (cond-mat.str-el) #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.2210.08563
published in arXiv (Cornell University) (Cornell University)
openalex publication_date 2022/10/16 · openalex created_date 2022/10/20 · openalex updated_date 2026/08/05
We study the semi-metal/insulator quantum phase transition in three-dimensional Dirac semi-metals by solving a set of Schwinger-Dyson equations. We study the effect of an anisotropic fermion velocity on the critical coupling of the transition. We consider the influence of several different approximations that are commonly used in the literature and show that results for the critical coupling change considerably when some of these approximations are relaxed. Most importantly, the nature of the dependence of the critical coupling on the anisotropy depends strongly on the approximations that are used for the photon polarization tensor. On the one hand, this means that calculations that include full photon dynamics are necessary to answer even the basic question of whether the critical coupling increases or decreases with anisotropy. On the other hand, our results mean that it is possible that anisotropy could provide a mechanism to promote dynamical gap generation in realistic three-dimensional Dirac semi-metallic materials.