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Updated: May 22, 2026
08:03
Study of Protein Dynamics via Neutron Spin Echo Spectroscopy
Published on: April 13, 2022
Dynamics of one electron in a nonlinear disordered chain
F A B F de Moura1, R A Caetano, B Santos
1Instituto de Física, Universidade Federal de Alagoas, Maceió, Brazil. fidelis@fis.ufal.br
Summary
Nonlinear hopping in the disordered Schrödinger equation can lead to long-time subdiffusion. This study explores electron-phonon interactions using an effective Schrödinger equation, revealing new numerical results.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Nonlinear dynamics
Background:
- The disordered Schrödinger equation models quantum systems with random potentials.
- Nonlinear hopping terms introduce complex interactions beyond standard linear models.
- Understanding electron-phonon interactions is crucial for material properties.
Purpose of the Study:
- To investigate the effects of nonlinear hopping on electron dynamics in disordered systems.
- To model the interaction between a single electron and acoustical phonons.
- To analyze the long-time behavior of wavepackets in such systems.
Main Methods:
- Derivation of an effective Schrödinger equation using a classical harmonic Hamiltonian and the Su-Schrieffer-Heeger approximation.
- Numerical solution of the effective Schrödinger equation with nonlinear hopping.
- Employment of a predictor-corrector Adams-Bashforth-Moulton method for wavepacket evolution.
Main Results:
- The nonlinear off-diagonal term was found to significantly influence wavepacket dynamics.
- A long-time subdiffusive regime was observed, characteristic of nonlinear systems.
- Comparison with models featuring diagonal nonlinearity showed similar subdiffusive behavior.
Conclusions:
- Off-diagonal nonlinearity in the disordered Schrödinger equation can induce subdiffusive transport.
- The findings contribute to understanding complex electron-phonon interactions in disordered quantum systems.
- Numerical results provide insights into the long-time dynamics of localized wavepackets.
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