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arXiv · 2303.04690

Quantum order by disorder in Frustrated Spin Nanotubes

João C. Getelina·Zekun Zhuang·Premala Chandra·Piers Coleman·Peter P. Orth·S. L. Sondhi
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Abstract

We investigate quantum order by disorder in a frustrated spin nanotube formed by wrapping a $J_1$-$J_2$ Heisenberg model at 45$^\circ$ around a cylinder. Using Schwinger boson theory and Density Matrix Renormalization Group (DMRG), we have computed the ground-state phase diagram to reveal a $\mathbb{Z}_2$ phase in which collinear spin stripes form a right or left handed helix around the nanotube. We have derived an analytic estimate for the critical $\eta_c=J_1/2J_2$ of the $\mathbb{Z}_2$ helical phase transition, which is in agreement with the DMRG results. By evaluating the entanglement spectrum and nonlocal string order parameters we discuss the topology of the $\mathbb{Z}_2$-helical phase.

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João C. Getelina, Zekun Zhuang, Premala Chandra, Piers Coleman, Peter P. Orth, S. L. Sondhi. 2023-03-08. Quantum order by disorder in Frustrated Spin Nanotubes. https://doi.org/10.1103/physrevb.109.075137

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