Abstract

Quantum computers promise to be more efficient and powerful than their classical counterparts. In the one-way quantum computer model [1], a sequence of measurements processes qubits, which are initially prepared in a highly entangled cluster state. We present here an optical implementation of a 4-qubit cluster state and we show how different algorithms can be experimentally realized by performing the corresponding sequence of measurements. The key advantage of this scheme over the standard network approach of quantum computing is that inherent, randomly induced measurement errors can classically be fed-forward and corrected by adapting the basis of subsequent measurements. Active feed-forward is therefore crucial to achieve deterministic quantum computing once a cluster state is prepared. We have recently experimentally realized [2] such a deterministic one-way quantum computation scheme by employing up to three active-switching Electro-Optical Modulators (EOM) in a four-qubit cluster state encoded into the polarization state of four photons [Fig.1].

© 2007 IEEE