Related Experiment Video
Updated: Jun 9, 2025
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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
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Evolution of the surface phase transitions in IrTe2
Govinda Kharal1, Bryan L Chavez1, Silu Huang1
1SmartState Center for Experimental Nanoscale Physics, Department of Physics and Astronomy, University of South Carolina, Columbia, SC, 29208, USA.
Scientific Reports
|October 22, 2024
Summary
Investigating iridium ditelluride (IrTe2) phase transitions using second harmonic generation (SHG) reveals distinct symmetries. The study clarifies transition temperatures and symmetries, explaining literature variations and uncovering a low-temperature trigonal phase.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid State Chemistry
Background:
- Iridium ditelluride (IrTe2) exhibits complex phase transitions.
- The precise symmetry of each phase in IrTe2 remains debated in scientific literature.
Purpose of the Study:
- To investigate the temperature-dependent symmetry evolution of IrTe2.
- To clarify the phase transitions and associated symmetries using advanced optical techniques.
Main Methods:
- Second harmonic generation (SHG) measurements were performed across a wide temperature range (4-300 K).
- SHG polarimetry was employed to probe the material's symmetry properties.
Main Results:
- Two distinct transition temperatures (Ts1 and Ts2) were identified, explaining variations in reported data.
- Trigonal symmetry was confirmed above Ts1, triclinic symmetry between Ts1 and Ts2, and multiple stripe phases below Ts2.
- A reentrant trigonal phase with six-fold symmetry was observed below ~10 K.
Conclusions:
- The study elucidates the complex phase diagram of IrTe2 by precisely mapping its symmetries.
- The findings provide a unified explanation for previously conflicting experimental results.
- The low-temperature trigonal phase is highlighted as crucial for understanding observed phenomena.
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