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arXiv · 1812.05615

Unifying Interacting Nodal Semimetals: A New Route to Strong Coupling

Shouvik Sur·Bitan Roy
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Abstract

We propose a general framework for constructing a large set of nodal-point semimetals by tuning the number of linearly ($d_L$) and (at most) quadratically ($d_Q$) dispersing directions. By virtue of such a unifying scheme, we identify a new perturbative route to access various strongly interacting non-Dirac semimetals with $d_Q>0$. As a demonstrative example, we relate a two dimensional anisotropic semimetal with $d_L=d_Q=1$, describing the topological transition between a Dirac semimetal and a normal insulator, and its three dimensional counterparts with $d_L=1$, $d_Q=2$. We address the quantum critical phenomena and emergence of non-Fermi liquid states with unusual dynamical structures within the framework of an $ε$ expansion, where $ε=2-d_Q$, when these systems reside at the brink of charge- or spin-density-wave orderings, or an $s$-wave pairing. Our results can be germane to two-dimensional uniaxially strained optical honeymcomb lattice, $α$-(BEDT-TTF)$_2\text{I}_3$.

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BibTeXRIS

Shouvik Sur, Bitan Roy. 2019-11-14. Unifying Interacting Nodal Semimetals: A New Route to Strong Coupling. https://doi.org/10.1103/physrevlett.123.207601

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