Experimental preparation of two-photon Knill-Laflamme-Milburn states
Karel Lemr, Antonín Černoch, Jan Soubusta, Jaromı́r Fiurášek · Physical Review A · 2010
We report an experimental preparation of the so-called Knill-Laflamme-Milburn states (KLM states) that have been known to have interesting properties related to quantum information processing. Our experiment has demonstrated successful preparation of entangled two-photon four-mode KLM states using spontaneous parametric down-conversion as a source of entangled photon pairs, linear optical components, and avalanche photodiodes for single-photon detection. We have verified the successful generation of KLM states by complete quantum state tomography.