Critical behavior at the mott-anderson transition: a typical-medium theory perspective.

Area of Science:

• Condensed Matter Physics
• Quantum Mechanics
• Materials Science

Background:

• The Mott-Anderson transition describes the interplay between electron-electron interactions (Mott localization) and disorder (Anderson localization).
• Understanding this transition is crucial for explaining the behavior of strongly correlated electron systems in disordered materials.

Purpose of the Study:

• To analyze the critical behavior near the Mott-Anderson transition.
• To investigate the influence of disorder and particle-hole symmetry on this transition.
• To elucidate the underlying electronic behavior at the transition point.

Main Methods:

• Utilized a combination of numerical and analytical techniques.
• Employed typical-medium theory, an extension of dynamical mean-field theory.
• Incorporated Anderson localization effects and scaling studies of Anderson impurity models.

Main Results:

• Identified a distinct two-fluid behavior at the Mott-Anderson transition under strong disorder.
• Demonstrated that only a fraction of electrons experience site-selective Mott localization.
• Showed that the remaining electrons transform into Anderson-localized quasiparticles.

Conclusions:

• The Mott-Anderson transition exhibits complex behavior dependent on disorder strength and particle-hole symmetry.
• The two-fluid model provides a new framework for understanding electron localization in disordered correlated systems.
• This work offers insights into the fundamental mechanisms governing metal-insulator transitions.