Phenomenon of multiple reentrant localization in a double-stranded helix with transverse electric field

Sudin Ganguly; Suparna Sarkar; Kallol Mondal; Santanu K. Maiti

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arXiv · 2306.14452

Phenomenon of multiple reentrant localization in a double-stranded helix with transverse electric field

Sudin Ganguly·Suparna Sarkar·Kallol Mondal·Santanu K. Maiti

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Abstract

The present work explores the potential for observing multiple reentrant localization behavior in a double-stranded helical (DSH) system, extending beyond the conventional nearest-neighbor hopping interaction. The DSH system is considered to have hopping dimerization in each strand, while also being subjected to a transverse electric field. The inclusion of an electric field serves the dual purpose of inducing quasiperiodic disorder and strand-wise staggered site energies. Two reentrant localization regions are identified: one exhibiting true extended behavior in the thermodynamic limit, while the second region shows quasi-extended characteristics with partial spreading within the helix. The DSH system exhibits three distinct single-particle mobility edges linked to localization transitions present in the system. The analysis in this study involves examining various parameters such as the single-particle energy spectrum, inverse participation ratio, local probability amplitude, and more. Our proposal, combining achievable hopping dimerization and induced correlated disorder, presents a unique opportunity to study phenomenon of reentrant localization, generating significant research interest.

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Sudin Ganguly, Suparna Sarkar, Kallol Mondal, Santanu K. Maiti. 2023-07-10. Phenomenon of multiple reentrant localization in a double-stranded helix with transverse electric field. https://arxiv.org/abs/2306.14452

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