Physical qubits from charged particles: Infrared divergences in quantum information

Journal Article · Fri May 15 00:00:00 EDT 2009 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.79.052309· OSTI ID:21300817

Leon, Juan; Martin-Martinez, Eduardo ^[1]

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1. Instituto de Fisica Fundamental, CSIC, Serrano 113-B, 28006 Madrid (Spain)

We consider soft-photon effects (ir structure of QED) on the construction of physical qubits. Soft photons appear when we build charged qubits from the asymptotic states of QED. This construction is necessary in order to include the effect of soft photons on entanglement measures. The nonexistence of free charged particles (due to the long range of QED interactions) leads us to question the sense of the very concept of free charged qubit. In this work, using the ''dressing'' formalism, we build physical charged qubits from dressed fields which have the correct asymptotic behavior, are gauge invariant, have propagators with a particle pole structure, and are free from infrared divergences. Finally, we discuss the impact of the soft corrections on the entanglement measures.

• OSTI ID: 21300817
• Journal Information: Physical Review. A, Vol. 79, Issue 5; Other Information: DOI: 10.1103/PhysRevA.79.052309; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ASYMPTOTIC SOLUTIONS
CHARGED PARTICLES
CORRECTIONS
GAUGE INVARIANCE
INFORMATION THEORY
INFRARED DIVERGENCES
PHOTONS
PROPAGATOR
QUANTUM COMPUTERS
QUANTUM ELECTRODYNAMICS
QUANTUM ENTANGLEMENT
QUBITS