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Shot Noise in a Metal Close to the Mott Transition
Yiou Zhang1, Shashi Pandey2, Sergei Ivanov1
1Department of Physics, Emory University, Atlanta, Georgia 30322, United States.
Nano Letters
|December 9, 2024
Summary
Shot noise measurements reveal that conduction in strontium iridate (SrIrO3) is not due to typical electron movement. Instead, collective electron hopping, influenced by strong correlations, mediates metallic conduction in this quantum material.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Strontium iridate (SrIrO3) is a complex oxide exhibiting unusual electronic and magnetic properties.
- These properties are linked to electron correlations near the Mott metal-insulator transition.
- The precise electronic state and conduction mechanisms in SrIrO3 are not well understood.
Purpose of the Study:
- To investigate the electronic state and conduction mechanism in nanoscale SrIrO3 junctions.
- To determine the nature of charge transport in SrIrO3.
- To explore the utility of shot noise measurements in studying quantum materials.
Main Methods:
- Fabrication and measurement of nanoscale SrIrO3 junctions.
- Analysis of shot noise suppression in these junctions.
- Investigation of thermal effects and length scaling of conduction.
Main Results:
- Shot noise in SrIrO3 junctions is significantly suppressed, contradicting diffusive quasiparticle transport models.
- Conduction is mediated by collective hopping of correlated, nearly localized electrons.
- Thermal effects and junction length influence the observed conduction properties.
Conclusions:
- The study provides insights into the non-Fermi liquid state of SrIrO3 near the Mott transition.
- Collective electron hopping is identified as the primary conduction mechanism.
- Shot noise measurements are validated as a powerful tool for probing quantum materials.
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