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Updated: Aug 15, 2025
06:24
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
6.5K
Nematic phases and elastoresistivity from a multiorbital non-Fermi liquid
Andrew Hardy1, Arijit Haldar1, Arun Paramekanti1
1Department of Physics, University of Toronto, Toronto, ON M5S 1A7, Canada.
Summary
We introduce a new model of correlated electrons, revealing novel nematic phases. These phases, arising from orbital polarization, impact material properties and offer insights into electronic transport.
Area of Science:
- Condensed Matter Physics
- Quantum Materials Science
Background:
- The Sachdev-Ye-Kitaev (SYK) model is a key theoretical framework for understanding quantum entanglement and many-body chaos.
- Multiorbital systems are crucial for emergent electronic phenomena like nematicity.
Purpose of the Study:
- To investigate a two-orbital lattice extension of the SYK model.
- To explore the phase diagram and emergent electronic phases in the large-N limit.
- To analyze the spectral and transport properties related to nematicity.
Main Methods:
- Large-N limit analysis of a two-orbital lattice SYK model.
- Investigation of thermal transitions and phase boundaries.
- Calculation of spectral functions and transport coefficients (elastoresistivity, elastoconductivity).
Main Results:
- Identified a phase diagram with isotropic non-Fermi liquid, nematic insulator, and nematic metal phases.
- Discovered a tunable tricritical point separating these phases.
- Observed spontaneous partial orbital polarization driving nematicity.
- DC elastoresistivity peaks near the nematic transition.
Conclusions:
- The proposed model provides a new perspective on correlated multiorbital systems.
- Spontaneous orbital polarization is a key mechanism for generating nematic phases.
- The findings offer insights into electronic transport phenomena in nematic materials.
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