Electronically smectic-like phase in a nearly half-doped manganite

TL;DR

This study reveals a smectic-like magnetic phase in a nearly half-doped manganite, showing complex spin and charge orderings that resemble liquid crystal textures, driven by spin-orbit interactions.

Contribution

It uncovers a novel smectic-like magnetic phase in a doped manganite, highlighting textured electronic soft phases in Mott insulators.

Findings

Identification of a smectic liquid-crystal-like magnetic phase

Observation of highly anisotropic spin textures above Neel temperature

Demonstration of spin-orbit interaction's role in phase formation

Abstract

We use neutron scattering to study the spin and charge/orbital ordering (CO-OO) in the nearly half-doped perovskite manganite $Pr_{0.55}(Ca_{0.8}Sr_{0.2})_{0.45}MnO_3$ (PCSMO). On cooling from room temperature, PCSMO first enters into a CO-OO state below $T_{CO}$ and then becomes a CE-type long-range ordered antiferromagnet below $T_N$. At temperatures above $T_N$ but below $T_{CO}$ ($T_N<T<T_{CO}$), the spins in PCSMO form highly anisotropic smectic liquid-crystal-like texture with ferromagnetic (FM) quasi-long-range ordered one-dimensional zigzag chains weakly coupled antiferromagnetically. Such a magnetic smectic-like phase results directly from the spin-orbit interaction and demonstrates the presence of textured `electronic soft' phases in doped Mott insulators.