Relationship between degree of polarization and two-time degree of coherence of electromagnetic fields

• DOI: 10.1007/s00340-021-07614-9
• Publication Date: 2021-04-20T08:04:02Z
• Authors: Rajneesh Joshi; Nishant Kumar Pathak; Bhaskar Kanseri
• Keywords: 0103 physical sciences; 01 natural sciences; 7. Clean energy

For stationary light fields, the degree of polarization (DOP) of light relates to the maximum correlation between two arbitrarily decomposed orthogonal electric field components at a space–time point. We generalize this understanding theoretically by showing a physically insightful connection between DOP and the two-time degree of coherence of electromagnetic fields. Further, by using a variable path Mach–Zehnder interferometer, we experimentally demonstrate that the DOP of light can be directly determined by measuring the correlation between orthogonal electric field components at two-time points, showing an excellent match between the experiment and the theory. This study also leads to methods for constructing a tunable DOP source.