Showing 2003 · quant-phShow all

11 papers · 2 filters

quant-ph2003★ 3 cited

Quantum Lower Bounds for Fanout

Maosen Fang, Stephen Fenner, Frederic Green +2

We prove several new lower bounds for constant depth quantum circuits. The main result is that parity (and hence fanout) requires log depth circuits, when the circuits are composed…

quant-ph2003★ 110 cited

Entangled-Photon Imaging of a Pure Phase Object

Ayman F. Abouraddy, Patrick R. Stone, Alexander V. Sergienko +2

We demonstrate experimentally and theoretically that a coherent image of a pure phase object may be obtained by use of a spatially incoherent illumination beam. This is accomplishe…

quant-ph2003

Symmetric Autocompensating Quantum Key Distribution

Zachary D. Walton, Alexander V. Sergienko, Lev B. Levitin +2

We present quantum key distribution schemes which are autocompensating (require no alignment) and symmetric (Alice and Bob receive photons from a central source) for both polarizat…

quant-ph2003★ 70 cited

Quantum Mechanical Ground State of Hydrogen Obtained from Classical Electrodynamics

Daniel C. Cole, Yi Zou

The behavior of a classical charged point particle under the influence of only a Coulombic binding potential and classical electromagnetic zero-point radiation, is shown to yield a…

quant-ph2003★ 59 cited

Entanglement, Mixedness, and Spin-Flip Symmetry in Multiple-Qubit Systems

Gregg Jaeger, Alexander V. Sergienko, Bahaa E. A. Saleh +1

A relationship between a recently introduced multipartite entanglement measure, state mixedness, and spin-flip symmetry is established for any finite number of qubits. It is also s…

quant-ph2003★ 55 cited

Observation of bosonic coalescence of photon pairs

Giovanni Di Giuseppe, Mete Atature, Matthew D. Shaw +6

Quantum theory predicts that two indistinguishable photons incident on a beam-splitter interferometer stick together as they exit the device (the pair emerges randomly from one por…

quant-ph2003

Information between quantum systems via POVMs

Lev B. Levitin, Tommaso Toffoli

The concepts of `conditional entropy' and `information' retain their validity for quantum systems, but their properties differ somewhat from those of their classical counterparts;…

quant-ph2003★ 340 cited

Demonstration of Dispersion-Cancelled Quantum-Optical Coherence Tomography

Magued B. Nasr, Bahaa E. A. Saleh, Alexander V. Sergienko +1

We present an experimental demonstration of quantum optical coherence tomography (QOCT). The technique makes use of an entangled twin-photon light source to carry out axial optical…

quant-ph2003★ 203 cited

Decoherence-Free Subspaces in Quantum Key Distribution

Zachary D. Walton, Ayman F. Abouraddy, Alexander V. Sergienko +2

We demonstrate that two recent innovations in the field of practical quantum key distribution (one-way autocompensation and passive detection) are closely related to the methods de…

quant-ph2003★ 110 cited

Effective fiber-coupling of entangled photons for quantum communication

F. A. Bovino, P. Varisco, A. M. Colla +3

We report on theoretical and experimental demonstration of high-efficiency coupling of two-photon entangled states produced in the nonlinear process of spontaneous parametric down…

quant-ph2003★ 40 cited

A multi-photon Stokes-parameter invariant for entangled states

Gregg Jaeger, Mihail Teodorescu-Frumosu, Alexander Sergienko +2

We consider the Minkowskian norm of the n-photon Stokes tensor, a scalar invariant under the group realized by the transformations of stochastic local quantum operations and classi…