Realizing the Potential of Quantum Information Processing

Štěpán Holub

Charles Santori, David A. Fattal, S. M. Spillane +14 more

We describe how a quantum non-demolition device based on electromagnetically-induced transparency in solidstate atom-like systems could be realized. Such a resource, requiring only weak optical nonlinearities, could potentially enable photonic quantum information processing (QIP) that is much more efficient than QIP based on linear optics alone. As an example, we show how a parity gate could be constructed. A particularly interesting physical system for constructing devices is the nitrogen-vacancy defect in diamond, but the excited-state structure for this system is unclear in the existing literature. We include some of our latest spectroscopic results that indicate that the optical transitions are generally not spin-preserving, even at zero magnetic field, which allows the realization of a Λ-type system.

Charles Santori, David A. Fattal, S. M. Spillane +14 more

We describe how a quantum non-demolition device based on electromagnetically-induced transparency in solidstate atom-like systems could be realized. Such a resource, requiring only weak optical nonlinearities, could potentially enable photonic quantum information processing (QIP) that is much more efficient than QIP based on linear optics alone. As an example, we show how a parity gate could be constructed. A particularly interesting physical system for constructing devices is the nitrogen-vacancy defect in diamond, but the excited-state structure for this system is unclear in the existing literature. We include some of our latest spectroscopic results that indicate that the optical transitions are generally not spin-preserving, even at zero magnetic field, which allows the realization of a Λ-type system.

Gilles Brassard A

Ian A. Walmsley, Michael G. Raymer

Quantum mechanics promises a much more powerful information-processing technology than is possible using classical physics. Photons offer one potentially important platform for encoding and manipulating information using the rules of quantum physics. In order to realize this potential, they must interact with each other, something that they are not normally inclined to do. However, as discussed in the Perspective by Walmsley and Raymer, it is possible using a combination of standard optical elements and detectors to synthesize an effective interaction provided all the photons used have identical properties. An important direction of current research is to develop sources of identical photons.

J. I. Cirac