Near-optimal single-photon sources in the solid state
A single photon with near-unity indistinguishability is generated from quantum dots in electrically controlled cavity structures. The cavity allows for efficient photon collection while application…
Generation of optical phase singularities by computer-generated holograms.
Laser beams that contain phase singularities can be generated with computer-generated holograms, which in the simplest case have the form of spiral Fresnel zone plates.
Demonstration of an all-optical quantum controlled-NOT gate
An unambiguous experimental demonstration and comprehensive characterization of quantum CNOT operation in an optical system that produces all four entangled Bell states as a function of only the input qubits' logical values, for a single operating condition of the gate.
Towards quantum chemistry on a quantum computer.
The application of the latest photonic quantum computer technology to calculate properties of the smallest molecular system: the hydrogen molecule in a minimal basis is reported and the complete energy spectrum is calculated to 20 bits of precision.
Linear optical controlled- NOT gate in the coincidence basis
We describe the operation and tolerances of a nondeterministic, coincidence basis, quantum controlled-NOT gate for photonic qubits. It is constructed solely from linear optical elements and requires…
Quantum process tomography of a controlled-NOT gate.
We demonstrate complete characterization of a two-qubit entangling process--a linear optics controlled-NOT gate operating with coincident detection--by quantum process tomography. We use a…
Discrete single-photon quantum walks with tunable decoherence.
- M. Broome, A. Fedrizzi, B. Lanyon, I. Kassal, Alán Aspuru-Guzik, A. G. White
- PhysicsPhysical Review Letters
- 26 February 2010
This work presents an intrinsically stable, deterministic implementation of discrete quantum walks with single photons in space, measures walks with up to 6 steps and explores the quantum-to-classical transition by introducing tunable decoherence.
High-efficiency Quantum Interrogation Measurements via the Quantum Zeno Effect
The phenomenon of quantum interrogation allows one to optically detect the presence of an absorbing object, without the measuring light interacting with it. In an application of the quantum Zeno…
Experimental quantum computing without entanglement.
The results show that even fully separable, highly mixed, states can contain intrinsically quantum mechanical correlations and that these could offer a valuable resource for quantum information technologies.
Experimental verification of decoherence-free subspaces.
Using spontaneous parametric down-conversion, we produce polarization-entangled states of two photons and characterize them using two-photon tomography to measure the density matrix. A controllable…