Nonlocality in Quantum Computing

✍ Scribed by J.D. Franson; T.B. Pittman

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 179 KB
• Volume: 46
• Category: Article
• ISSN: 0015-8208
• DOI: 10.1002/(sici)1521-3978(199811)46:6/8<697::aid-prop697>3.0.co;2-a

✦ Synopsis

The operation of a quantum computer is inherently nonlocal due to the entanglement of separated quantum gates. This paper is concerned instead with the use of nonlocal effects to construct the quantum gates themselves. A nonlocal interaction in which pairs of atoms exchange two photons is expected to produce a large nonlinear phase shift. An interesting feature of this effect is that energy is not conserved at the location of an individual atom but it is conserved overall. The preliminary results from a series of experiments in a sodium vapor cell are in apparent agreement with the predictions of the theory. These nonlinear phase shifts can be used to construct quantum logic gates, such as a Controlled-NOT.