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arXiv · 1812.01045

First-Order Topological Quantum Phase Transition in a Strongly Correlated Ladder

S. Barbarino·G. Sangiovanni·J. C. Budich
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Abstract

We report on the discovery of a quantum tri-critical point (QTP) separating a line of first-order topological quantum phase transitions from a continuous transition regime in a strongly correlated one-dimensional lattice system. Specifically, we study a fermionic four-leg ladder supporting a symmetry-protected topological phase in the presence of on-site interaction, which is driven towards a trivial gapped phase by a nearest-neighbor interaction. Based on DMRG simulations, we show that, as a function of the interaction strength, the phase transition between the topological and the trivial phase switches from being continuous to exhibiting a first-order character. Remarkably, the QTP as well as the first-order character of the topological transition in the strongly correlated regime are found to clearly manifest in simple local observables.

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S. Barbarino, G. Sangiovanni, J. C. Budich. 2018-12-03. First-Order Topological Quantum Phase Transition in a Strongly Correlated Ladder. https://doi.org/10.1103/physrevb.99.075158

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