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Updated: Apr 10, 2026
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
9.3K
Quantum ferroelectricity in charge-transfer complex crystals.
Sachio Horiuchi1, Kensuke Kobayashi2, Reiji Kumai3
11] National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8562, Japan [2] CREST, Japan Science and Technology Agency (JST), Tokyo 102-0076, Japan.
Nature Communications
|June 17, 2015
Summary
Researchers explored quantum phase transitions in novel ferroelectric charge-transfer complexes. TTF-QBr2I2 exhibits a unique neutral-ionic phase transition tunable with pressure, showing enhanced permittivity near quantum criticality.
Area of Science:
- Solid state science
- Materials science
- Condensed matter physics
Background:
- Quantum phase transitions (QPTs) occur at absolute zero, driven by quantum fluctuations.
- Studying QPTs is crucial for understanding critical phenomena beyond thermal effects.
- Ferroelectric charge-transfer complexes offer a platform to investigate QPTs.
Purpose of the Study:
- To synthesize and investigate novel tetrahalo-p-benzoquinone (QBr4-nIn) compounds.
- To search for ferroelectric charge-transfer complexes with tetrathiafulvalene (TTF).
- To explore pressure-tuned quantum critical behavior in these materials.
Main Methods:
- Chemical synthesis of pure tetrahalo-p-benzoquinones (QBr4-nIn, n=0-4).
- Formation of charge-transfer complexes with tetrathiafulvalene (TTF).
- Investigation of neutral-ionic phase transitions under hydrostatic pressure and varying temperatures.
Main Results:
- TTF-QBr2I2 demonstrated a ferroelectric neutral-ionic phase transition tunable from near-zero Kelvin to room temperature via pressure.
- This transition exhibited quantum critical behavior with significantly enhanced permittivity.
- TTF-QBr3I showed suppression of its ferroelectric spin-Peierls-type phase transition.
Conclusions:
- Novel TTF-based complexes provide a tunable platform for studying quantum phase transitions.
- TTF-QBr2I2 is a promising material for exploring quantum criticality and ferroelectricity.
- Chemical substitution influences the nature and suppression of phase transitions in these systems.
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