Tripartite non-maximally-entangled mixed states as a resource for optimally controlled quantum teleportation fidelity

Abstract

Three-qubit mixed states are used as channel for controlled quantum teleportation (CQT) of single qubit states. The connection between different channel parameters to achieve maximum controlled teleportation fidelity is investigated. We show that for a given multipartite entanglement and mixedness, a new class of non-maximally entangled mixed X states (X−NMEMS) achieve optimum controlled quantum teleportation fidelity, interestingly a class of maximally entangled mixed X states (X−MEMS) fails to do so. This demonstrates, for a given spectrum and mixedness, X−MEMS is not sufficient to attain optimum controlled quantum teleportation fidelity, which is in contradiction with the traditional quantum teleportation of single qubits. In addition, we show that biseparable X−NMEMS for certain range of mixedness are useful as a resource to attain high controlled quantum teleportation fidelity, which essentially lower the requirements of quantum channels for CQT.I.

Quantum speed limit time: role of coherence as a dynamical witness to distinguish multi-qubit entangled states

“…The presence of quantum coherence prompts the emergence of many intriguing properties of the quantum system. Quantum coherence and quantum correlations as a resource play a pivotal role in wide range of fields; quantum information processing, quantum metrology, and quantum thermodynamics [14][15][16][17][18][19][20][21][22]. In the literature, two different approaches have been proposed to quantify coherence; viz.…”

Phase covariant channel: Quantum speed limit of evolution

“…In general, (non)-Markovianity discusses the nature of correlations that the system possesses with the environment. Quantum coherence and correlations are significant resources for quantum technology [8][9][10][11][12]. Non-Markovianity influences the quantum resources in both beneficial and unfavourable ways; consequently, the investigation of quantum correlation and coherence becomes highly significant [13][14][15].…”

Quantum speed limit for the creation and decay of quantum correlations

“…The existence of quantum correlations and coherence in a system is a valuable resource for many tasks of fundamental and practical importance. The uncontested supremacy of certain protocols in quantum regime over classical counterparts in the field of quantum metrol-ogy, quantum communication, quantum thermodynamics, [14,15] etc., is achieved by manipulating and controlling quantum correlations and coherence. The interwoven connection between the coherence and quantum entanglement [16,17] signifies the need of harnessing their stronger interdependence and the fundamental speed limit at which a system reveals its quantumness.…”