Quantum communication with coherent states of light

Quantum Communication Complexity with Coherent States and Linear Optics

We introduce a general mapping for encoding quantum communication protocols involving pure states of multiple qubits, unitary transformations, and projective measurements into another set of protocols that employ coherent states of light in a superposition of optical modes, linear optics transformations and measurements with single-photon threshold detectors. This provides a general framework f...

Quantum memory receiver for superadditive communication using binary coherent states

We propose a simple architecture based on multimode quantum memories for collective readout of classical information keyed using a pair coherent states, exemplified by the well-known binary phase shift keying format. Such a configuration enables demonstration of the superadditivity effect in classical communication over quantum channels, where the transmission rate becomes enhanced through join...

Optical Communication with Weak Coherent Light Fields

Quantum repeaters with entangled coherent states

Nicolas Sangouard,* Christoph Simon, Nicolas Gisin, Julien Laurat, Rosa Tualle-Brouri, and Philippe Grangier Group of Applied Physics-Optics, University of Geneva, CH-1211 Geneva 4, Switzerland Matériaux et Phènomènes Quantiques, CNRS UMR 7162, Université Paris Diderot, 75013 Paris France Institute for Quantum Information Science and Department of Physics and Astronomy, University of Calgary, C...

Quantum metrology with entangled coherent states.

We present an improved phase estimation scheme employing entangled coherent states and demonstrate that these states give the smallest variance in the phase parameter in comparison to NOON, "bat," and "optimal" states under perfect and lossy conditions. As these advantages emerge for very modest particle numbers, the optical version of entangled coherent state metrology is achievable with curre...