Realization of a Knill-Laflamme-Milburn controlled-NOT photonic quantum circuit combining effective optical nonlinearities
Open Access
- 6 June 2011
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 108 (25), 10067-10071
- https://doi.org/10.1073/pnas.1018839108
Abstract
Quantum information science addresses how uniquely quantum mechanical phenomena such as superposition and entanglement can enhance communication, information processing, and precision measurement. Photons are appealing for their low-noise, light-speed transmission and ease of manipulation using conventional optical components. However, the lack of highly efficient optical Kerr nonlinearities at the single photon level was a major obstacle. In a breakthrough, Knill, Laflamme, and Milburn (KLM) showed that such an efficient nonlinearity can be achieved using only linear optical elements, auxiliary photons, and measurement [Knill E, Laflamme R, Milburn GJ (2001) Nature 409:46–52]. KLM proposed a heralded controlled-NOT (CNOT) gate for scalable quantum computation using a photonic quantum circuit to combine two such nonlinear elements. Here we experimentally demonstrate a KLM CNOT gate. We developed a stable architecture to realize the required four-photon network of nested multiple interferometers based on a displaced-Sagnac interferometer and several partially polarizing beamsplitters. This result confirms the first step in the original KLM “recipe” for all-optical quantum computation, and should be useful for on-demand entanglement generation and purification. Optical quantum circuits combining giant optical nonlinearities may find wide applications in quantum information processing, communication, and sensing.This publication has 42 references indexed in Scilit:
- Teleportation-based realization of an optical quantum two-qubit entangling gateProceedings of the National Academy of Sciences of the United States of America, 2010
- Quantum computersNature, 2010
- Towards quantum chemistry on a quantum computerNature Chemistry, 2010
- Silica-on-Silicon Waveguide Quantum CircuitsScience, 2008
- Linear optical quantum computing with photonic qubitsReviews of Modern Physics, 2007
- Spatiotemporal few-photon optical nonlinearities through linear optics and measurementPhysical Review A, 2004
- Demonstration of an all-optical quantum controlled-NOT gateNature, 2003
- Optical simulation of quantum logicPhysical Review A, 1998
- Giant Kerr nonlinearities obtained by electromagnetically induced transparencyOptics Letters, 1996
- Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channelsPhysical Review Letters, 1993