Related Experiment Video
Updated: Oct 31, 2025
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Anisotropic magnetoresistance and memory effect in bulk systems with extended defects
K S Denisov1, K A Baryshnikov1, P S Alekseev1
1Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia.
Summary
Memory effects in 3D conductors with 1D defects cause strong negative magnetoresistance when magnetic fields align with defects. This reveals a new way to detect these defects.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Electron scattering in disordered conductors is often modeled using the Boltzmann equation, assuming independent scattering events.
- Correlations between scattering events become crucial in magnetic fields, leading to memory effects.
- These memory effects explain phenomena like giant negative magnetoresistance in 2D systems.
Purpose of the Study:
- To investigate memory effects in 3D conducting systems with one-dimensional (1D) defects.
- To explore the impact of electron trajectories around 1D defects on conductivity.
- To determine if these effects can induce significant magnetoresistance.
Main Methods:
- Theoretical analysis of electron scattering in the presence of 1D defects.
- Incorporation of electron capture on collisionless spiral trajectories.
- Calculation of resistivity under external magnetic fields parallel to defect axes.
Main Results:
- Memory effects, specifically electron capture on spiral trajectories around 1D defects, induce strong negative magnetoresistance.
- This magnetoresistance occurs when the magnetic field is parallel to the 1D defect axis.
- Significant magnetoresistance anisotropy is observed even with an isotropic Fermi surface and no spin-orbit effects.
Conclusions:
- Memory effects in 3D conductors with 1D defects lead to a pronounced negative magnetoresistance.
- The observed magnetoresistance anisotropy provides a signature for the presence of 1D scattering defects.
- This effect offers a potential method for detecting 1D defects in conducting materials.
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