The simplest form for the correlation matrix of a completely unpolarized electromagnetic beam is the product of a scalar correlation function times a unit matrix. We show, however, that classes of unpolarized beams exist for which the diagonal elements of the correlation matrix are not equal to each other and the off-diagonal elements do not vanish identically. This gives rise to a distinction between pure and impure unpolarized beams. The two types of beams can be distinguished at the experimental level by their behavior in a Young’s interferometer.
© 2009 Optical Society of America
Original Manuscript: February 27, 2009
Manuscript Accepted: March 31, 2009
Published: April 30, 2009
Franco Gori, Jani Tervo, and Jari Turunen, "Correlation matrices of completely unpolarized beams," Opt. Lett. 34, 1447-1449 (2009)