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arXiv · 2311.05000

Quantum Phase Transitions in Skewed Ladder Systems

Sambunath Das·Dayasindhu Dey·Rajamani Raghunathan·Zoltán G. Soos·Manoranjan Kumar·S. Ramasesha
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Abstract

In this brief review, we introduce a new spin ladder system called skewed spin ladders and discuss the exotic quantum phases of this system. The spin ladders studied are the 5/7, 3/4 and 3/5 systems corresponding to alternately fused 5 and 7 membered rings; 3 and 4 membered rings; and 3 and 5 membered rings. These ladders show completely different behaviour as the Hamiltonian model parameter is changed. When the Hamiltonian parameter is increased the 5/7 ladder switches from an initial singlet ground state to progressively higher spin ground state and then to a reentrant singlet state before finally settling to the highest spin ground state whose spin equals the number of unit cells in the system. The 3/4 ladder goes from a singlet ground state to a high spin ground state with each unit cell contributing spin 1 to the state, as the model parameter is increased. The 3/5 ladder shows a singlet ground state for small parameters and high spin ground state for intermediate values of the parameter and for still higher parameters, a reentrant singlet ground state. They can also show interesting magnetization plateaus as illustrated by studies on a specific spin ladder.

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Sambunath Das, Dayasindhu Dey, Rajamani Raghunathan, Zoltán G. Soos, Manoranjan Kumar, S. Ramasesha. 2023-11-08. Quantum Phase Transitions in Skewed Ladder Systems. https://doi.org/10.1039/d3cp04179d

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