Magnetic Memory Effects in BaFe2(As0.68P0.32)2 Superconducting Single Crystal
Alina M Badea Ionescu1, Ion Ivan1, Corneliu F Miclea1
1National Institute of Materials Physics, 405A Atomistilor Str., 077125 Magurele, Romania.
Materials (Basel, Switzerland)
|November 9, 2024
Summary
Researchers found a magnetic memory effect in iron-based superconductors related to structural transitions. This effect influences vortex dynamics beyond the usual Second Magnetization Peak (SMP).
Area of Science:
- Condensed Matter Physics
- Materials Science
- Superconductivity
Background:
- Isovalently substituted BaFe2(As1-xPx)2 is an iron-based superconductor.
- This material exhibits a Second Magnetization Peak (SMP) in critical current density versus magnetic field.
- An unusual peak effect in critical current density versus temperature is observed near the rhombic-to-square (RST) structural transition.
Purpose of the Study:
- To investigate the influence of the rhombic-to-square (RST) structural transition on vortex dynamics in BaFe2(As1-xPx)2.
- To explore the magnetic memory effect associated with the structural transition.
- To understand the relationship between structural transitions and vortex excitations.
Main Methods:
- Multi-harmonic AC susceptibility measurements were performed.
- Experiments were conducted under three cooling regimes: field cooling, zero-field cooling, and field cooling with warming.
- AC susceptibility was measured at different AC frequencies to probe time-scale differences.
Main Results:
- A pronounced magnetic memory effect was discovered in a specific temperature region, attributed to the direction of the structural transition.
- Significant differences in the third harmonic susceptibility at low and high AC frequencies indicate distinct timescales for structural transitions and vortex excitations.
- The influence of the RST structural transition on vortex dynamics extends beyond the onset of the Second Magnetization Peak (SMP).
Conclusions:
- The rhombic-to-square (RST) structural transition significantly impacts vortex dynamics in iron-based superconductors.
- A magnetic memory effect, linked to the direction of the structural transition, was identified.
- The findings reveal a complex interplay between structural changes and vortex behavior, influencing superconducting properties.
Keywords:
anomalous peak effectiron-based superconductorsmagnetic memory effectmulti-harmonic susceptibilityrhombic-to-square structural transitionMore Related Videos
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