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Relaxor Pb(Mg(1/3)Nb(2/3))O3: a ferroelectric with multiple inhomogeneities
Desheng Fu1, Hiroki Taniguchi, Mitsuru Itoh
1Division of Global Research Leaders, Shizuoka University, Johoku 3-5-1, Naka-ku, Hamamatsu 432-8561, Japan.
Physical Review Letters
|April 7, 2010
Summary
Giant dielectric response in lead magnesium niobate (PMN) relaxors stems from polarization reorientation. These relaxors are nanosized ferroelectric materials with complex domain structures, explaining their unique physical properties.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Dielectric Materials
Background:
- Lead magnesium niobate (Pb(Mg(1/3)Nb(2/3))O(3) or PMN) is a relaxor material known for its giant dielectric response.
- The fundamental nature of PMN's dielectric behavior and its physical ground state have been subjects of extensive research for decades.
- Previous studies highlighted chemical and local symmetry inhomogeneities in PMN relaxors.
Purpose of the Study:
- To comprehensively investigate the physical ground state and giant dielectric response of PMN relaxor crystals.
- To elucidate the mechanisms behind the anomalous dielectric behavior observed in PMN across a wide temperature range.
- To understand the role of inhomogeneities in the unique properties of PMN and similar relaxor systems.
Main Methods:
- Comprehensive experimental study of PMN relaxor crystals.
- Analysis of dielectric response across a broad temperature range.
- Investigation of polarization reorientation phenomena.
- Characterization of domain structure inhomogeneities at the nanoscale.
Main Results:
- The anomalous dielectric behavior of PMN is attributed to the reorientation of polarization within the crystal.
- PMN relaxors are identified as nanosized ferroelectric materials.
- The material exhibits multiscale inhomogeneities in its domain structure, in addition to chemical and local symmetry variations.
Conclusions:
- The complex interplay of polarization reorientation and multiscale structural inhomogeneities is key to PMN's giant dielectric effects.
- These inhomogeneities are crucial for the enigmatic physical properties observed in relaxor systems.
- The findings offer insights for designing novel materials with giant effects, potentially utilizing relaxor systems.
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