Experimental observation of quantum entanglement in low dimensional spin systems

TL;DR

This study experimentally investigates quantum entanglement in low-dimensional spin systems using magnetic susceptibility measurements, distinguishing phases and quantifying entanglement as functions of temperature and magnetic field.

Contribution

It demonstrates the use of magnetic susceptibility as an entanglement witness and distinguishes between random singlet and Griffiths phases in specific low-dimensional materials.

Findings

Quantified entanglement via magnetic susceptibility.

First experimental distinction between random singlet and Griffiths phases.

Demonstrated field-induced quantum entanglement in low-dimensional spin systems.

Abstract

We report macroscopic magnetic measurements carried out in order to detect and characterize field-induced quantum entanglement in low dimensional spin systems. We analyze the pyroborate MgMnB_2O_5 and the and the warwickite MgTiOBO_3, systems with spin 5/2 and 1/2 respectively. By using the magnetic susceptibility as an entanglement witness we are able to quantify entanglement as a function of temperature and magnetic field. In addition, we experimentally distinguish for the first time a random singlet phase from a Griffiths phase. This analysis opens the possibility of a more detailed characterization of low dimensional materials.