Arbitrarily Large Continuous-Variable Cluster States From a Single Quantum Nondemolition Gate

Phys Rev Lett. 2010 Jun 25;104(25):250503. doi: 10.1103/PhysRevLett.104.250503. Epub 2010 Jun 23.


We present a compact experimental design for producing an arbitrarily large optical continuous-variable cluster state using just one single-mode vacuum squeezer and one quantum nondemolition gate. Generating the cluster state and computing with it happen simultaneously: more entangled modes become available as previous modes are measured, thereby making finite the requirements for coherence and stability even as the computation length increases indefinitely.