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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Correlation matrices of completely unpolarized beams
Franco Gori1, Jani Tervo, Jari Turunen
1Dipartimento di Fisica, Università degli Studi "Roma Tre" and Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia (CNISM), Via della Vasca Navale 84, I00146 Rome, Italy.
Optics Letters
|May 5, 2009
Summary
Researchers discovered new types of unpolarized electromagnetic beams. These pure and impure unpolarized beams differ in their correlation matrix properties and can be experimentally distinguished using Young
Area of Science:
- Optics and Photonics
- Electromagnetic Theory
Background:
- The correlation matrix of unpolarized electromagnetic beams typically simplifies to a scalar correlation function multiplied by a unit matrix.
- This conventional model assumes equal diagonal elements and zero off-diagonal elements in the correlation matrix for unpolarized light.
Purpose of the Study:
- To investigate the existence and properties of unpolarized electromagnetic beams beyond the simplest model.
- To introduce a distinction between 'pure' and 'impure' unpolarized beams based on their correlation matrix structure.
Main Methods:
- Theoretical analysis of the correlation matrix for electromagnetic beams.
- Mathematical derivation to identify conditions for non-trivial correlation matrices in unpolarized beams.
Main Results:
- Demonstrated that classes of unpolarized beams exist where diagonal elements of the correlation matrix are unequal.
- Identified unpolarized beams with non-vanishing off-diagonal elements in the correlation matrix.
- Established that these findings lead to a classification of pure and impure unpolarized beams.
Conclusions:
- The conventional model of unpolarized beams is not exhaustive; more complex forms exist.
- Pure and impure unpolarized beams represent distinct classes with unique correlation matrix characteristics.
- Experimental differentiation of these beam types is achievable through interference experiments, specifically using a Young's interferometer.
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