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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Observation of a multiferroic critical end point
Jae Wook Kim1, S Y Haam, Y S Oh
1Center for Strongly Correlated Materials Research and Frontier Physics Research Division, Department of Physics and Astronomy, Seoul National University, Seoul 151-742, South Korea.
Summary
Researchers discovered a magnetic-field-induced metaelectric transition in multiferroic BiMn(2)O(5). This transition, analogous to metamagnetic transitions, shows critical behavior near zero temperature, offering new physics insights.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism and Ferroelectricity
Background:
- Metamagnetic transitions in itinerant electron systems reveal new physics and quantum critical points.
- The electric analogue, a "metaelectric" critical end point, is less explored.
- Multiferroic materials offer a platform to study field-induced transitions due to coupled magnetism and ferroelectricity.
Purpose of the Study:
- To investigate the existence and characteristics of a magnetic-field-induced metaelectric critical end point.
- To explore the behavior of multiferroic BiMn(2)O(5) under varying magnetic fields and temperatures.
- To understand the interplay between magnetic and electric properties in multiferroics.
Main Methods:
- Applied magnetic fields (H) to multiferroic BiMn(2)O(5) samples.
- Measured electric polarization (P) and dielectric constant (epsilon) as a function of magnetic field and temperature (T).
- Analyzed the transition behavior and power-law characteristics near critical points.
Main Results:
- Discovered a magnetic-field-induced metaelectric transition in BiMn(2)O(5) at a critical magnetic field H(c).
- Observed a simultaneous spin-flop transition in Mn spins concurrent with the electric polarization (P) switching.
- Found that transitions sharpen upon cooling but remain a continuous cross-over down to 0.5 K, with significant dielectric constant (epsilon) enhancement near the P=0 line.
- Identified power-law behavior in P(H) and epsilon(H) at low temperatures (T = 0.66 K).
Conclusions:
- A magnetic-field-induced metaelectric critical end point is realized in multiferroic BiMn(2)O(5).
- The material exhibits unique critical phenomena near zero temperature, driven by magnetic field.
- This discovery opens avenues for exploring novel electric and magnetic orders in multiferroic systems.
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