Concentration of higher dimensional entanglement: qutrits of photon orbital angular momentum

Phys Rev Lett. 2003 Nov 28;91(22):227902. doi: 10.1103/PhysRevLett.91.227902. Epub 2003 Nov 26.


Enhancement of entanglement is necessary for most quantum communication protocols many of which are defined in Hilbert spaces larger than 2. In this work we present the experimental realization of entanglement concentration of orbital angular momentum entangled photons. We investigate the specific case of three dimensions and the possibility of generating different entangled states out of an initial state. The results presented here are of importance for pure states as well as for mixed states.