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. © 2003 The American Physical Society.
Vaziri Alipasha;Pan Jian-Wei;Jennewein Thomas;Zeilinger Anton;Weihs Gregor
Physical Review Letters