The possibility of nonlocal quantum communication is considered. We investigate three $gedankenexperiments$ that have variable entanglement: (1) a 4-detector polarization-entangled system, (2) a 4-detector path-entangled system, and (3) a 3-detector path-entangled system that uses an innovative optical mixer to combine photon paths. A new quantum paradox is reviewed in which the presence or absence of an interference pattern in a path-entangled two photon system, controlled by measurement choice, is a potential nonlocal signal. We show that for the cases considered, even when interference patterns can be switched off and on, there is always a "signal" interference pattern and an "anti-signal" interference pattern that mask any observable interference when they are added, even when entanglement and coherence are simultaneously present. This behavior can be attributed to what in the literature has been called "the complementarity of one- and two-particle interference".The possibility of nonlocal quantum communication is considered. We investigate three $gedankenexperiments$ that have variable entanglement: (1) a 4-detector polarization-entangled system, (2) a 4-detector path-entangled system, and (3) a 3-detector path-entangled system that uses an innovative optical mixer to combine photon paths. A new quantum paradox is reviewed in which the presence or absence of an interference pattern in a path-entangled two photon system, controlled by measurement choice, is a potential nonlocal signal. We show that for the cases considered, even when interference patterns can be switched off and on, there is always a "signal" interference pattern and an "anti-signal" interference pattern that mask any observable interference when they are added, even when entanglement and coherence are simultaneously present. This behavior can be attributed to what in the literature has been called "the complementarity of one- and two-particle interference".

arXiv:1409.5098Sep 17, 20146 citations

Destruction of interference by entanglement

Lawrence S. Schulman

Physics Letters AFeb 1, 199621 citations

An Inquiry into the Possibility of Nonlocal Quantum Communication

J. G. Cramer

The possibility of nonlocal quantum communication is considered. We investigate three gedankenexperiments that have variable entanglement: (1) a 4-detector polarization-entangled system, (2) a 4-detector path-entangled system, and (3) a 3-detector path-entangled system that uses an innovative optical mixer to combine photon paths. A new quantum paradox is reviewed in which the presence or absence of an interference pattern in a path-entangled two photon system, controlled by measurement choice, is a potential nonlocal signal. We show that for the cases considered, even when interference patterns can be switched off and on, there is always a “signal” interference pattern and an “anti-signal” interference pattern that mask any observable interference when they are added, even when entanglement and coherence are simultaneously present. This behavior can be attributed to what in the literature has been called “the complementarity of one- and two-particle interference”.The possibility of nonlocal quantum communication is considered. We investigate three gedankenexperiments that have variable entanglement: (1) a 4-detector polarization-entangled system, (2) a 4-detector path-entangled system, and (3) a 3-detector path-entangled system that uses an innovative optical mixer to combine photon paths. A new quantum paradox is reviewed in which the presence or absence of an interference pattern in a path-entangled two photon system, controlled by measurement choice, is a potential nonlocal signal. We show that for the cases considered, even when interference patterns can be switched off and on, there is always a “signal” interference pattern and an “anti-signal” interference pattern that mask any observable interference when they are added, even when entanglement and coherence are simultaneously present. This behavior can be attributed to what in the literature has been called “the complementarity of one- and two-particle interference”.

Jun 1, 20180 citations

Entanglement and Decoherence

Andreas Buchleitner, Carlos Viviescas, Markus Tiersch

Lecture notes in physicsNov 7, 200857 citations

On Entanglement-Suppressed Single-Photon Interference

Aleksandr V. Belinsky

Abstract Schemes to measure the presence or absence of interference depending on the entangled or nonentangled states in an initial biphoton field are proposed. The disappearance of interference in the ‘‘which way’’ scheme is shown to have nothing to do with the direct impact of the detector on the explored system. Sufficient information is provided by the channel that is used by a passing particle. It is shown that entanglement suppresses the one-photon interference but does not suppress biphoton interference, which can be observed using a scheme similar to the Franson type interference. Calculations are presented that confirm the efficiency of the proposed approach and our conclusions.Abstract Schemes to measure the presence or absence of interference depending on the entangled or nonentangled states in an initial biphoton field are proposed. The disappearance of interference in the ‘‘which way’’ scheme is shown to have nothing to do with the direct impact of the detector on the explored system. Sufficient information is provided by the channel that is used by a passing particle. It is shown that entanglement suppresses the one-photon interference but does not suppress biphoton interference, which can be observed using a scheme similar to the Franson type interference. Calculations are presented that confirm the efficiency of the proposed approach and our conclusions.

Moscow University Physics BulletinDec 1, 20201 citation

Quantum Entanglement

Masahito Hayashi, Satoshi Ishizaka, Akinori Kawachi +2 more

Graduate texts in physicsAug 22, 20140 citations

The possibility of nonlocal quantum communication is considered. We investigate three

gedankenexperiments

that have variable entanglement: (1) a 4-detector polarization-entangled system, (2) a 4-detector path-entangled system, and (3) a 3-detector path-entangled system that uses an innovative optical mixer to combine photon paths. A new quantum paradox is reviewed in which the presence or absence of an interference pattern in a path-entangled two photon system, controlled by measurement choice, is a potential nonlocal signal. We show that for the cases considered, even when interference patterns can be switched off and on, there is always a "signal" interference pattern and an "anti-signal" interference pattern that mask any observable interference when they are added, even when entanglement and coherence are simultaneously present. This behavior can be attributed to what in the literature has been called "the complementarity of one- and two-particle interference".