Weak nonlinearities: a new route to optical quantum computation

Abstract

Quantum information processing (QIP) offers the promise of being able to do\nthings that we cannot do with conventional technology. Here we present a new\nroute for distributed optical QIP, based on generalized quantum non-demolition\nmeasurements, providing a unified approach for quantum communication and\ncomputing. Interactions between photons are generated using weak\nnon-linearities and intense laser fields--the use of such fields provides for\nrobust distribution of quantum information. Our approach requires only a\npractical set of resources, and it uses these very efficiently. Thus it\npromises to be extremely useful for the first quantum technologies, based on\nscarce resources. Furthermore, in the longer term this approach provides both\noptions and scalability for efficient many-qubit QIP.\n