Dipolar Ordering and Quantum Dynamics of Domain Walls in Mn-12 Acetate

TL;DR

This paper investigates how dipolar interactions induce ferromagnetic order in Mn12 Acetate crystals below 0.8 K, analyzing domain wall structures and their quantum dynamics through Landau-Zener transitions.

Contribution

It provides a detailed theoretical analysis of domain wall structure and mobility in Mn12 Acetate, highlighting the quantum nature of their dynamics and robustness against decoherence.

Findings

Dipolar interactions lead to ferromagnetic ordering below 0.8 K.

Domain walls facilitate quantum Landau-Zener transitions.

Wall structure and mobility are theoretically characterized.

Abstract

We find that dipolar interactions favor ferromagnetic ordering of elongated crystals of Mn12 Acetate below 0.8 K. Ordered crystals must possess domain walls. Motion of the wall corresponds to a moving front of Landau-Zener transitions between quantum spin levels. Structure and mobility of the wall are computed. The effect is robust with respect to inhomogeneous broadening and decoherence.