Qubit devices and the issue of quantum decoherence

Abstract

The exciting new field of quantum information science and technology is burgeoning with revolutionary new advances in the areas of quantum communication, quantum information processing, quantum computing, and quantum cryptography. Potential useful products of these advances include a wide variety of innovative qubit devices, ranging from quantum games and quantum teleporters to quantum computers and quantum robots. The major obstacle to the successful development of these devices is the phenomenon of quantum decoherence. This brief survey article gives reviews of a full gamut of potential qubit devices, alternating with expository discussions of the issue of quantum decoherence as it relates to the possible practical development of these devices. The qubit devices examined here include an interaction-free detector, a quantum key receiver, quantum games, various quantum gates, qubit entanglers, quantum dense coders, Bell-state analyzers, entanglement swappers, quantum teleporters, quantum repeaters, entangled atomic clocks, quantum copiers, various quantum computers, and quantum robots.