How a dc Electric Field Drives Mott Insulators Out of Equilibrium

Area of Science:

• Condensed Matter Physics
• Materials Science
• Non-equilibrium Physics

Background:

• Out-of-equilibrium phenomena are crucial in modern physics.
• Correlated materials, like Mott insulators, exhibit exotic long-lived states under strong electric fields.
• The precise mechanism of electric field-induced destabilization in these materials remains unclear.

Purpose of the Study:

• To comprehensively investigate the electrical response of Mott insulators GaM4Q8 (M=V, Nb, Ta, Mo; Q=S, Se).
• To elucidate the microscopic origins of electrical breakdown in these correlated materials.
• To understand the role of in-gap states in the electrical response.

Main Methods:

• Conducted a detailed study of the electrical response of canonical Mott insulators.
• Employed a microscopic theory of electrical breakdown.
• Utilized a two-temperature model to describe the system's behavior.

Main Results:

• Demonstrated that nonlinearities and resistive transitions arise from the massive creation of hot electrons under an electric field.
• Identified the generation of in-gap states as a key factor in the electrical breakdown process.
• Provided a clear link between electric field strength and electron excitation.

Conclusions:

• The study elucidates the mechanism of electric field-induced destabilization in Mott insulators.
• Findings offer new insights for controlling long-lived exotic states in these materials.
• Results pave the way for novel functionalities in neuromorphic applications.