Chiral Magnetic Effect of Hot Electrons

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Phenomena

Background:

• The chiral magnetic effect (CME) is a quantum phenomenon observed in Weyl semimetals.
• Observing CME typically requires specific conditions and sensitive detection methods.
• Noncentrosymmetric Weyl semimetals exhibit unique electronic properties under electric fields.

Purpose of the Study:

• To propose a novel method for observing the chiral magnetic effect in noncentrosymmetric Weyl semimetals.
• To utilize the nonlinear electrical characteristics, specifically the magnetic field-odd part of the I-V curve, for CME detection.
• To explore the role of valley-selective heating and resulting nonequilibrium valley population imbalances.

Main Methods:

• Applying a strong electric field to noncentrosymmetric Weyl semimetals.
• Analyzing the nonlinear current-voltage (I-V) characteristics, focusing on the magnetic field-odd component.
• Investigating valley-selective heating effects and their influence on valley population imbalances.
• Considering electrically open circuits to measure magnetic field-odd voltages.

Main Results:

• Valley-selective heating leads to nonequilibrium valley population imbalances in Weyl semimetals.
• In the presence of an external magnetic field, these imbalances generate an electric current along the magnetic field direction (CME).
• The proposed method allows for the observation of CME via nonlinear electrical transport signatures.

Conclusions:

• The nonlinear I-V characteristic, odd in the magnetic field, provides a viable pathway to observe the chiral magnetic effect.
• Valley-selective heating is identified as a key mechanism driving the CME in this experimental setup.
• The study suggests a specific experimental configuration for detecting the chiral magnetic effect of hot electrons.