Ultrafast Current Switching from Quantum Geometry in Semimetals

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Kim, Youngjae, Kim, Sejoong, Rhim, Jun-Won
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913047077978112
author Kim, Youngjae
Kim, Sejoong
Rhim, Jun-Won
author_facet Kim, Youngjae
Kim, Sejoong
Rhim, Jun-Won
contents Technological progress towards next-generation electronics critically relies on achieving faster switching with reduced energy consumption. Because device operation speeds are fundamentally constrained by the intrinsic properties of constituent materials, identifying systems with inherently superior switching capabilities is essential. Here, we propose that semimetallic systems characterized by non-trivial quantum geometry, including quadratic band-touching semimetals and singular flat bands, can serve as a promising platform for ultrafast switching at voltages compatible with modern electronics. We show that, in such quantum geometric semimetals, an electric current is generated instantaneously upon application of a moderate external electric field, reaching its steady-state value. As a consequence, the current exhibits rapid and stable on-off switching behaviour under periodic optical pulse trains, demonstrating robustness under experimentally feasible conditions. In terms of switching speed, this quantum geometric semimetal outperforms conventional metals, semiconductors, and graphene. We identify the microscopic origin of this behaviour as interband coupling governed by the Hilbert-Schmidt quantum distance, together with a finite density of states at the band-touching point. This mechanism further leads to a universal classification of conductivity for both gapless and gapped quantum geometric semimetals. Finally, first-principles calculations suggest realistic material platforms, including bilayer graphene, cyclic graphene, monolayer bismuth and V3F8-in which the predicted instantaneous current switching can be directly realized, further supported by time-dependent density functional theory simulations performed for representative systems.
format Preprint
id arxiv_https___arxiv_org_abs_2604_15924
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Ultrafast Current Switching from Quantum Geometry in Semimetals
Kim, Youngjae
Kim, Sejoong
Rhim, Jun-Won
Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
Materials Science
Quantum Physics
Technological progress towards next-generation electronics critically relies on achieving faster switching with reduced energy consumption. Because device operation speeds are fundamentally constrained by the intrinsic properties of constituent materials, identifying systems with inherently superior switching capabilities is essential. Here, we propose that semimetallic systems characterized by non-trivial quantum geometry, including quadratic band-touching semimetals and singular flat bands, can serve as a promising platform for ultrafast switching at voltages compatible with modern electronics. We show that, in such quantum geometric semimetals, an electric current is generated instantaneously upon application of a moderate external electric field, reaching its steady-state value. As a consequence, the current exhibits rapid and stable on-off switching behaviour under periodic optical pulse trains, demonstrating robustness under experimentally feasible conditions. In terms of switching speed, this quantum geometric semimetal outperforms conventional metals, semiconductors, and graphene. We identify the microscopic origin of this behaviour as interband coupling governed by the Hilbert-Schmidt quantum distance, together with a finite density of states at the band-touching point. This mechanism further leads to a universal classification of conductivity for both gapless and gapped quantum geometric semimetals. Finally, first-principles calculations suggest realistic material platforms, including bilayer graphene, cyclic graphene, monolayer bismuth and V3F8-in which the predicted instantaneous current switching can be directly realized, further supported by time-dependent density functional theory simulations performed for representative systems.
title Ultrafast Current Switching from Quantum Geometry in Semimetals
topic Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
Materials Science
Quantum Physics
url https://arxiv.org/abs/2604.15924