Abstract

Despite a wide range of applications, the coherence theory of random, nonstationary (pulsed or otherwise) electromagnetic fields is far from complete. In this work, we show that full coherence of a nonstationary vectorial field at a pair of spatiospectral points is equivalent to the factorization of the cross-spectral density matrix, and full pointwise coherence over a spatial volume and spectral band leads to a factored cross-spectral density throughout the domain. We further show that in the latter case, the time-domain mutual coherence matrix factors in the spatiotemporal variables, and the field is temporally fully coherent throughout the volume. The results of this work justify that certain expressions of random pulsed electromagnetic beams appearing in the literature can be called coherent-mode representations.

© 2021 Optical Society of America

Cross-spectral purity of the Stokes parameters in random nonstationary electromagnetic beams

Jyrki Laatikainen, Ari T. Friberg, and Tero Setälä
Opt. Lett. 48(21) 5823-5826 (2023)

Polarization of completely coherent random electromagnetic beams

Kisik Kim and Emil Wolf
Opt. Lett. 31(2) 146-148 (2006)

Complete electromagnetic coherence in the space–frequency domain

Tero Setälä, Jani Tervo, and Ari T. Friberg
Opt. Lett. 29(4) 328-330 (2004)

Poincaré sphere of electromagnetic spatial coherence

Jyrki Laatikainen, Ari T. Friberg, Olga Korotkova, and Tero Setälä
Opt. Lett. 46(9) 2143-2146 (2021)

Interferometry and coherence of nonstationary light

Matias Koivurova, Lutful Ahad, Gianluca Geloni, Tero Setälä, Jari Turunen, and Ari T. Friberg
Opt. Lett. 44(3) 522-525 (2019)