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arXiv · 1708.06985

Order in Quantum Compass and Orbital $e_g$ Models

Piotr Czarnik·Jacek Dziarmaga·Andrzej M. Oleś
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Abstract

We investigate thermodynamic phase transitions in the compass model and in $e_g$ orbital model on an infinite square lattice by variational tensor network renormalization (VTNR) in imaginary time. The onset of nematic order in the quantum compass model is estimated at ${\cal T}_c/J=0.0606(4)$. For~the $e_g$ orbital model one finds: ($i$) a very accurate estimate of ${\cal T}_c/J=0.3566\pm 0.0001$ and ($ii$)~the~critical exponents in the Ising universality class. Remarkably large difference in frustration results in so distinct values of ${\cal T}_c$, while entanglement influences the quality of ${\cal T}_c$ estimation.

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Piotr Czarnik, Jacek Dziarmaga, Andrzej M. Oleś. 2017-08-23. Order in Quantum Compass and Orbital $e_g$ Models. https://doi.org/10.12693/aphyspola.133.359

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