State Dependent and Independent cloner: Cloning and Broadcasting

TL;DR

This paper explores the broadcasting of entanglement using various state dependent and independent quantum cloning machines, analyzing their effectiveness on different two-qubit states and identifying scenarios where state dependent cloners outperform independent ones.

Contribution

It introduces and characterizes static and dynamic state dependent cloners, deriving conditions for their independence from input states, and compares their performance in entanglement broadcasting.

Findings

State dependent cloners can outperform state independent cloners in certain broadcasting scenarios.

The work provides a comprehensive analysis of entanglement broadcasting across various two-qubit states.

Conditions for making cloners input-state independent are derived.

Abstract

In this work, we extensively study the problem of broadcasting of entanglement. In the first part of the work, we reconceptualize the idea of state dependent quantum cloning machine, and in that process we introduce different types of state dependent cloners like static and dynamic state dependent cloners. We derive the conditions under which we can make these cloners independent of the input state. In the broadcasting part, as our resource initial state, we start with general two qubit state and consider specific examples like, non maximally entangled state (NME), Werner like state (WS), and Bell diagonal state (BDS). We apply both state dependent/ state independent cloners, both locally and non-locally, in each of these cases. Incidentally, we find several instances where state dependent cloners outperform state independent cloners in broadcasting. This work gives us a holistic view on the broadcasting of entanglement in various two qubit states, when we have an almost exhaustive sets of cloning machines in our arsenal