Ultrafast Current Switching from Quantum Geometry in Semimetals

• URL: http://arxiv.org/abs/2604.15924v2
• Date: Mon, 20 Apr 2026 17:47:03 GMT
• Title: Ultrafast Current Switching from Quantum Geometry in Semimetals
• Abstract summary: Non-trivial quantum geometric semimetals can serve as a promising platform for ultrafast switching at voltages compatible with modern electronics.<n>In terms of switching speed, this quantum geometric semimetal outperforms conventional metals, semiconductors, and graphene.<n>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.
• Score: 1.8566949733257492
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: 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.

Related papers

• Using near-flat-band electrons for read-out of molecular spin qubit entangled states [2.024757499000596]
  Molecular spin qubits (MSQs) are a promising platform for quantum computing.<n>We show electrical read-out of entangled MSQs via driven many-electron spin unpolarized currents.
  arXiv  Detail & Related papers  (2026-02-24T19:41:53Z)
• Quantum master equation for nanoelectromechanical systems beyond the wide-band limit [0.0]
  We derive a quantum master equation that describes nanoelectromechanical systems in a generally overlooked situation.<n>We go beyond the wide-band limit and study the consequence of maintaining energy dependent tunneling rates.<n>We derive from the microscopic model a ready to use particle current expression that replicates features already observed experimentally.
  arXiv  Detail & Related papers  (2025-06-25T16:32:13Z)
• Electron-Electron Interactions in Device Simulation via Non-equilibrium Green's Functions and the GW Approximation [71.63026504030766]
  electron-electron (e-e) interactions must be explicitly incorporated in quantum transport simulation.<n>This study is the first one reporting large-scale atomistic quantum transport simulations of nano-devices under non-equilibrium conditions.
  arXiv  Detail & Related papers  (2024-12-17T15:05:33Z)
• Thermalization and Criticality on an Analog-Digital Quantum Simulator [133.58336306417294]
  We present a quantum simulator comprising 69 superconducting qubits which supports both universal quantum gates and high-fidelity analog evolution. We observe signatures of the classical Kosterlitz-Thouless phase transition, as well as strong deviations from Kibble-Zurek scaling predictions. We digitally prepare the system in pairwise-entangled dimer states and image the transport of energy and vorticity during thermalization.
  arXiv  Detail & Related papers  (2024-05-27T17:40:39Z)
• Efficient electron transfer in quantum dot chains controlled by a cubic detuning profile via shortcuts to adiabaticity [0.0]
  We study theoretically the control of shuttling of an electron along a linear chain of semiconductor quantum dots. A given fidelity can be set experimentally by controlling the maximum sweep energy and duration of the control pulse.
  arXiv  Detail & Related papers  (2022-06-03T20:23:08Z)
• Resonant tunneling diodes in semiconductor microcavities: modeling polaritonic features in the THz displacement current [0.0]
  The effect of the quantized electromagnetic field in the displacement current of a resonant tunneling diode is analyzed. This mimics known effects predicted by a Jaynes-Cummings model in closed systems. The computational burden involved in the multi-time measurements of THz currents is tackled by invoking a Bohmian description of the light-matter interaction.
  arXiv  Detail & Related papers  (2022-04-27T10:51:03Z)
• Slowing down light in a qubit metamaterial [98.00295925462214]
  superconducting circuits in the microwave domain still lack such devices. We demonstrate slowing down electromagnetic waves in a superconducting metamaterial composed of eight qubits coupled to a common waveguide. Our findings demonstrate high flexibility of superconducting circuits to realize custom band structures.
  arXiv  Detail & Related papers  (2022-02-14T20:55:10Z)
• Fast high-fidelity single-qubit gates for flip-flop qubits in silicon [68.8204255655161]
  flip-flop qubit is encoded in the states with antiparallel donor-bound electron and donor nuclear spins in silicon. We study the multilevel system that is formed by the interacting electron and nuclear spins. We propose an optimal control scheme that produces fast and robust single-qubit gates in the presence of low-frequency noise.
  arXiv  Detail & Related papers  (2021-01-27T18:37:30Z)
• Waveguide quantum optomechanics: parity-time phase transitions in ultrastrong coupling regime [125.99533416395765]
  We show that the simplest set-up of two qubits, harmonically trapped over an optical waveguide, enables the ultrastrong coupling regime of the quantum optomechanical interaction. The combination of the inherent open nature of the system and the strong optomechanical coupling leads to emerging parity-time (PT) symmetry. The $mathcalPT$ phase transition drives long-living subradiant states, observable in the state-of-the-art waveguide QED setups.
  arXiv  Detail & Related papers  (2020-07-04T11:02:20Z)
• Entanglement generation via power-of-SWAP operations between dynamic electron-spin qubits [62.997667081978825]
  Surface acoustic waves (SAWs) can create moving quantum dots in piezoelectric materials. We show how electron-spin qubits located on dynamic quantum dots can be entangled.
  arXiv  Detail & Related papers  (2020-01-15T19:00:01Z)
• Decoherence Effects Break Reciprocity in Matter Transport [0.0]
  We present nanoscale devices in which decoherence, modeled by random quantum jumps, produces fundamentally novel phenomena by interrupting the unitary dynamics of electron wave packets. In these devices, the inelastic interaction of itinerant electrons with impurities acting as electron trapping centers leads to a novel steady state characterized by partial charge separation between the two leads. The interface between the quantum and the classical worlds therefore provides a novel transport regime of value for the realization of a new category of mesoscopic electronic devices.
  arXiv  Detail & Related papers  (2019-12-27T00:07:20Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.