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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference

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Characterizing disordered fermion systems using the momentum-space entanglement spectrum.

Ian Mondragon-Shem¹, Mayukh Khan¹, Taylor L Hughes¹

¹Department of Physics, University of Illinois, 1110 West Green Street, Urbana, Illinois 61801, USA.

Physical Review Letters

|August 29, 2014

Summary

Researchers propose momentum-space entanglement spectrum to characterize disordered models. This method reveals delocalized states and phase transitions in quantum systems, offering clear results from single diagonalizations.

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Area of Science:

Condensed matter physics
Quantum entanglement
Disordered quantum systems

Background:

Quantum entanglement is crucial for studying critical and topological phases in condensed matter.
Real-space entanglement characterizes localized and delocalized phases in disordered fermion systems.

Purpose of the Study:

To introduce and validate the momentum-space entanglement spectrum for characterizing disordered quantum models.
To demonstrate its effectiveness in identifying delocalized states and phase transitions.

Main Methods:

Developing and applying the momentum-space entanglement spectrum analysis.
Investigating one-dimensional disordered fermion models with spatially correlated disorder.
Utilizing single numerical diagonalization for data acquisition.

Main Results:

Momentum-space entanglement characterizes localization in one dimension.
The spectrum clearly identifies delocalized states within the energy spectrum.
It serves as a signature for phase transitions between localized and delocalized phases.

Conclusions:

Momentum-space entanglement is a powerful tool for analyzing disordered quantum systems.
This approach simplifies the characterization of localization and phase transitions.
It offers a computationally efficient method requiring only a single diagonalization.