Nonexponential relaxations in a two-dimensional electron system in silicon

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Electronics

Background:

• Strongly disordered two-dimensional (2D) electron systems exhibit complex behavior under non-equilibrium conditions.
• Understanding charge carrier dynamics is crucial for developing advanced electronic devices.

Purpose of the Study:

• To investigate the conductivity relaxations in a disordered 2D electron system in silicon.
• To explore the influence of carrier density and temperature on out-of-equilibrium dynamics.
• To elucidate the role of Coulomb interactions in these phenomena.

Main Methods:

• Studied conductivity relaxations in a silicon-based 2D electron system.
• Utilized rapid changes in carrier density (ns) to induce non-equilibrium states.
• Performed experiments at low temperatures (T).

Main Results:

• Observed dramatic and precise dependence of conductivity relaxations on carrier density and temperature.
• Data strongly suggests a transition to a glassy phase as temperature approaches zero (T-->0).
• Evidence indicates Coulomb interactions significantly influence the observed out-of-equilibrium dynamics.

Conclusions:

• The study provides strong evidence for a temperature-driven glassy phase transition in disordered 2D electron systems.
• Coulomb interactions are identified as a dominant factor governing the non-equilibrium dynamics.
• Findings contribute to the fundamental understanding of electron behavior in strongly correlated systems.