Entanglement, purity, and energy: Two qubits versus two modes

Journal Article · Sun Oct 15 04:00:00 EDT 2006 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.74.042303· OSTI ID:20857821

McHugh, Derek ^[1]; Ziman, Mario ^[1]; Buzek, Vladimir ^[1]

---

1. Research Center for Quantum Information, Slovak Academy of Sciences, Dubravska cesta 9, 84511 Bratislava (Slovakia)

We study the relationship between the entanglement, mixedness, and energy of two-qubit and two-mode Gaussian quantum states. We parametrize the set of allowed states of these two fundamentally different physical systems using measures of entanglement, mixedness, and energy that allow us to compare and contrast the two systems using a phase diagram. This phase diagram enables one to clearly identify not only the physically allowed states, but the set of states connected under an arbitrary quantum operation. We pay particular attention to the maximally entangled mixed states of each system. Following this we investigate how efficiently one may transfer entanglement from two-mode to two-qubit states.

• OSTI ID: 20857821
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 74; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
COMPARATIVE EVALUATIONS
ENERGY LEVELS
MIXED STATE
OPERATION
PHASE DIAGRAMS
QUANTUM COMPUTERS
QUANTUM ENTANGLEMENT
QUANTUM MECHANICS
QUANTUM NUMBERS
QUBITS