Experimental study of quantum coherence decomposition and trade-off relations in a tripartite system

TL;DR

This paper experimentally investigates how quantum coherence is distributed and traded among parts of a tripartite quantum system, revealing trade-off relations, monogamy properties, and the utility of coherence as a state characterization tool.

Contribution

It provides the first experimental verification of coherence trade-off relations and monogamy inequalities in a tripartite quantum system with adiabatic state evolution.

Findings

Verified coherence trade-off relations in tripartite systems

Confirmed monogamy and polygamy properties of quantum coherence

Showed coherence properties are consistent across different state types

Abstract

Quantum coherence is the most fundamental of all quantum quantifiers, underlying other well-known quantities such as entanglement, quantum discord, and Bell correlations. It can be distributed in a multipartite system in various ways -- for example, in a bipartite system it can exist within subsystems (local coherence) or collectively between the subsystems (global coherence) and exhibits a trade-off relation. In quantum systems with more than two subsystems, there are more trade-off relations, due to the various decomposition ways of the coherence. In this paper, we experimentally verify these coherence trade-off relations in adiabatically evolved quantum systems using a spin system by changing the state from a product state to a tripartite entangled state. We study the full set of coherence trade-off relations between the original state, the bipartite product state, the tripartite product state, and the decohered product state. We also experimentally verify the monogamy inequality and show that both the quantum systems are polygamous except for the initial product state. We find that despite the different types of states involved, the properties of the state in terms of coherence and monogamy are equivalent. This illustrates the utility of using coherence as a characterization tool for quantum states.