Exploring quantum properties of bipartite mixed states under coherent and incoherent basis

Abstract

Quantum coherence and quantum entanglement are two different manifestations of the superposition principle. In this article we show that the right choice of basis to be used to estimate coherence is the separable basis. The quantum coherence estimated using the Bell basis does not represent the coherence in the system, since there is a coherence in the system due to the choice of the basis states. We first compute the entanglement and quantum coherence in the two qubit mixed states prepared using the Bell states and one of the states from the computational basis. The quantum coherence is estimated using the l1-norm of coherence, the entanglement is measured using the concurrence and the mixedness is measured using the linear entropy. Then we estimate these quantities in the Bell basis and establish that coherence should be measured only in separable basis, whereas entanglement and mixedness can be measured in any basis. We then calculate the teleportation fidelity of these mixed states and find the regions where the states have a fidelity greater than the classical teleportation fidelity. We also examine the violation of the Bell-CHSH inequality to verify the quantum nonlocal correlations in the system. The estimation of the above mentioned quantum correlations, teleportation fidelity and the verification of Bell-CHSH inequality is also done for bipartite states obtained from the tripartite systems by the tracing out of one of their qubits. We find that for some of these states teleportation is possible even when the Bell-CHSH inequality is not violated, signifying that nonlocality is not a necessary condition for quantum teleportation.

18 pages, 3 figures

References in corpus (19)

• Entanglement of Formation of an Arbitrary State of Two Qubits
• Separability Criterion for Density Matrices
• Separability of Mixed States: Necessary and Sufficient Conditions
• Concentrating Partial Entanglement by Local Operations
• Quantifying Coherence
• Four qubits can be entangled in nine different ways
• Frozen Quantum Coherence
• Maximizing the entanglement of two mixed qubits
• Classification of multi-qubit mixed states: separability and distillability properties
• Teleportation, Bell's Inequalities and Inseparability
• Distribution of quantum coherence in multipartite systems
• Alternative framework for quantifying coherence
• Mixed state sensitivity of several quantum information benchmarks
• Deterministic Coherence Distillation
• Multipartite entanglement in 2 x 2 x n quantum systems
• Estimating coherence measures from limited experimental data available
• Entanglement Manipulation and Concentration
• Mixed State Entanglement: Manipulating Polarisation-Entangled Photons
• Fragility of quantum correlations and coherence in a multipartite photonic system

Cited by in corpus (4)

• Non-maximally entangled mixed states of X and non-X types as teleportation channels
• Environment engineering to protect quantum coherence in tripartite systems under dephasing noise
• Symmetric and asymmetric tripartite states under the lens of entanglement splitting and topological linking
• Dephasing-Induced Distribution of Entanglement in Tripartite Quantum Systems