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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Some calculable contributions to entanglement entropy.
Mark P Hertzberg1, Frank Wilczek
1Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. mphertz@mit.edu
Physical Review Letters
|March 17, 2011
Summary
Researchers developed a method to calculate finite contributions to entanglement entropy in quantum systems. This approach considers parametric dependence on correlation length, yielding measurable results for scalar fields in various spatial domains and waveguides.
Area of Science:
- Quantum Information Theory
- Condensed Matter Physics
- Quantum Field Theory
Background:
- Entanglement entropy is crucial in quantum systems but often incalculable due to sensitivity to unknown microphysics.
- Existing methods struggle to provide precise, finite values for entanglement entropy in complex geometries.
Purpose of the Study:
- To develop a method for extracting finite, calculable contributions to entanglement entropy.
- To analyze the dependence of entanglement entropy on correlation length for scalar fields.
- To investigate contributions in arbitrary spatial domains and waveguide geometries.
Main Methods:
- Parametric dependence on correlation length was analyzed.
- Entanglement entropy was calculated for a scalar field between interior and exterior regions.
- Contributions in 3+1 dimensional waveguides were extracted, considering geometric properties.
Main Results:
- A leading term proportional to the boundary area was identified.
- Finite subleading contributions related to waveguide cross-sectional geometry (area, perimeter, curvature) were extracted.
- The method provides calculable contributions to entanglement entropy.
Conclusions:
- Finite, calculable contributions to entanglement entropy can be extracted by considering correlation length dependence.
- The extracted terms offer insights into the geometric dependence of entanglement entropy.
- These contributions may be measurable in specific physical systems, particularly at criticality.
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