Entanglement is an important ingredient for quantum information processing. We discuss some sources of entanglement, namely a beam splitter and a thermal field. For the generation of entangled continuous-variable states, we consider a beam splitter and find some conditions for input fields to see entanglement in the output. While a beam splitter is a unitary device to generate an entangled state for a bipartite continuous-variable system, a thermal field is shown to mediate entanglement of two qubits.Entanglement is an important ingredient for quantum information processing. We discuss some sources of entanglement, namely a beam splitter and a thermal field. For the generation of entangled continuous-variable states, we consider a beam splitter and find some conditions for input fields to see entanglement in the output. While a beam splitter is a unitary device to generate an entangled state for a bipartite continuous-variable system, a thermal field is shown to mediate entanglement of two qubits.

Fortschritte der PhysikMay 1, 20022 citations

Quantum Information Processing with Trapped Neutral Atoms

Poul Jessen, Ivan Deutsch, R. Stock

Quantum Information ProcessingOct 1, 200424 citations

Quantum Information Processing with Trapped Neutral Atoms

Poul Jessen, Ivan Deutsch, R. Stock

Springer eBooksApr 2, 20070 citations

Experimental realization of a resource-saving polarization-independent orbital-angular-momentum-preserving tunable beam splitter

Yaping Li, Fang‐Xiang Wang, Wei Chen +6 more

The tunable beam splitter (TBS) is a fundamental component used in optical experiments. A TBS can preserve the orbital angular momentum (OAM) states; in addition, the polarization states of photons are valuable for some particular experiments, such as high-dimensional quantum information processing. We use polarization beam splitters and half-wave plates to realize such a TBS under a compact structure, which can reduce the number of elements that require comparing with existing works. The experiments verify that the TBS has good performances in tunability, polarization, and OAM state preservation. A Sagnac interferometer is implemented with the proposed TBS to evaluate its practical usability, and the mean visibilities greater than 99.30% under varying polarization states demonstrate its potential for optical information processing.The tunable beam splitter (TBS) is a fundamental component used in optical experiments. A TBS can preserve the orbital angular momentum (OAM) states; in addition, the polarization states of photons are valuable for some particular experiments, such as high-dimensional quantum information processing. We use polarization beam splitters and half-wave plates to realize such a TBS under a compact structure, which can reduce the number of elements that require comparing with existing works. The experiments verify that the TBS has good performances in tunability, polarization, and OAM state preservation. A Sagnac interferometer is implemented with the proposed TBS to evaluate its practical usability, and the mean visibilities greater than 99.30% under varying polarization states demonstrate its potential for optical information processing.

Optics LettersJan 31, 20192 citations

Quantum information processing with atoms and photons

Christopher R. Monroe

NatureMar 1, 2002627 citations

Atom vortex beams

V. E. Lembessis, Demosthenes Ellinas, M. Babiker +1 more

The concept that all de Broglie particles can form vortex beams is analyzed for neutral atoms. It is shown how atoms diffracted from a suitably constructed optical mask configuration employing light of $l$ units of orbital angular momentum and at far-off resonance with an atomic transition can lead to the generation of a discrete set of atom vortex beams each endowed with the property of quantized orbital angular momentum about the beam axis in units of $\ensuremath{\hbar}l$. Selection criteria of atom vortex beams are derived and the functioning of the mask configuration for angular dispersion of beams in terms of de Broglie wavelength is analyzed. Prospects of applications in the areas of atom interferometry and dispersion, and quantum information processing via atom vortices are pointed out.The concept that all de Broglie particles can form vortex beams is analyzed for neutral atoms. It is shown how atoms diffracted from a suitably constructed optical mask configuration employing light of $l$ units of orbital angular momentum and at far-off resonance with an atomic transition can lead to the generation of a discrete set of atom vortex beams each endowed with the property of quantized orbital angular momentum about the beam axis in units of $\ensuremath{\hbar}l$. Selection criteria of atom vortex beams are derived and the functioning of the mask configuration for angular dispersion of beams in terms of de Broglie wavelength is analyzed. Prospects of applications in the areas of atom interferometry and dispersion, and quantum information processing via atom vortices are pointed out.

Physical Review AMay 15, 201461 citations

l

units of orbital angular momentum and at far-off resonance with an atomic transition can lead to the generation of a discrete set of atom vortex beams each endowed with the property of quantized orbital angular momentum about the beam axis in units of $\ensuremath{\hbar}l$. Selection criteria of atom vortex beams are derived and the functioning of the mask configuration for angular dispersion of beams in terms of de Broglie wavelength is analyzed. Prospects of applications in the areas of atom interferometry and dispersion, and quantum information processing via atom vortices are pointed out.