Elementary optical gate for expanding an entanglement web

Entanglement Structure in Expanding Universes

We investigate entanglement of a quantum field in de Sitter spacetime using a particle detector model. By considering the entanglement between two comoving detectors interacting with a scalar field, it is possible to detect the entanglement of the scalar field by swapping it to detectors. For the massless minimal scalar field, we find that the entanglement between the detectors cannot be detect...

Optical control of an ion channel gate.

The powerful optogenetic pharmacology method allows the optical control of neuronal activity by photoswitchable ligands tethered to channels and receptors. However, this approach is technically demanding, as it requires the design of pharmacologically active ligands. The development of versatile technologies therefore represents a challenging issue. Here, we present optogating, a method in whic...

Phase matching as a gate for photon entanglement

Phase matching is shown to provide a tunable gate that helps discriminate entangled states of light generated by four-wave mixing (FWM) in optical fibers against uncorrelated photons originating from Raman scattering. Two types of such gates are discussed. Phase-matching gates of the first type are possible in the normal dispersion regime, where FWM sidebands can be widely tuned by high-order d...

Scalable web page entanglement

We present a proxy-based system for augmenting the capabilities of the World Wide Web. Our system adds two-way association links and automatically removes these links when they break, while the existing web features only one-way links and lingering broken links. Several web augmentation systems have been developed in the past that add two-way links. Our key contribution is in terms of link mana...

Quantum optical Fredkin gate.