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Updated: Mar 7, 2026
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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Experimental Evidence for Static Charge Density Waves in Iron Oxypnictides
A Martinelli1, P Manfrinetti1,2, A Provino1,2
1SPIN-CNR, C.so Perrone 24, I- 16152 Genova-Italy.
Physical Review Letters
|February 18, 2017
Summary
Manganese substitution in LaFeAsO superconductors induces a static incommensurate modulated structure. This charge-density-wave instability is driven by electron density, impacting Fe-based superconductor physics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Crystallography
Background:
- Iron-based superconductors exhibit complex phase diagrams.
- Understanding structural transitions is key to optimizing superconducting properties.
- Manganese substitution is explored to tune electronic and magnetic behaviors.
Purpose of the Study:
- To investigate the structural evolution in Manganese-substituted LaFeAsO.
- To identify the nature of the low-temperature phase.
- To elucidate the driving mechanism of observed structural distortions.
Main Methods:
- High-resolution synchrotron X-ray powder diffraction.
- Transmission electron microscopy (TEM).
- Analysis of Mn-substituted LaFeAsO samples.
Main Results:
- A static incommensurate modulated structure was observed in the low-temperature orthorhombic phase.
- The modulation wave vector is dependent on the Manganese (Mn) content.
- Evidence suggests the distortion originates from a charge-density-wave instability.
Conclusions:
- The study reveals a novel incommensurate structural modulation in Mn-substituted LaFeAsO.
- The findings indicate that charge-density-wave ordering is the primary driver.
- This work contributes to a deeper understanding of the physics governing Fe-based superconductors.
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