Interferometric methods to measure orbital and spin, or the total angular momentum of a single photon

Phys Rev Lett. 2004 Jan 9;92(1):013601. doi: 10.1103/PhysRevLett.92.013601. Epub 2004 Jan 5.

Abstract

We propose interferometric methods capable of measuring either the total angular momentum, or simultaneously measuring the spin and orbital angular momentum of single photons. This development enables the measurement of any angular momentum eigenstate of a single photon. The work allows the investigation of single-photon two-qubit entangled states and has implications for high density information transfer.