Quantum percolation and magnetic nano-dropletstates in electronically phase-separated manganite nanowires

TL;DR

This study reveals how quasi-one-dimensional confinement in manganite nanowires influences magnetic fluctuations, phase stability, and quantum percolation, providing new insights into electronic inhomogeneity and phase transitions in low-dimensional systems.

Contribution

It demonstrates the impact of extreme aspect ratio nanowires on magnetic nano-droplet states and quantum percolation, establishing a new phase diagram for manganites under quasi-1D confinement.

Findings

Detection of magnetic nano-droplet states preceding ferromagnetic metallic phase

Stabilization of intrinsic tunneling junctions in low-temperature regimes

Modification of classic 1D percolation to a quantum percolation state

Abstract

One-dimensional (1D) confinement has been revealed to effectively tune the properties of materials in homogeneous states. The 1D physics can be further enriched by electronic inhomogeneity, which unfortunately remains largely unknown. Here we demonstrate the ultra-high sensitivity to magnetic fluctuations and the tunability of phase stability in the electronic transport properties of self-assembled electronically phase-separated manganite nanowires with extreme aspect ratio. The onset of magnetic nano-droplet state, a precursor to the ferromagnetic metallic state, is unambiguously revealed, which is attributed to the small lateral size of the nanowires that is comparable to the droplet size. Moreover, the quasi-1D anisotropy stabilizes thin insulating domains to form intrinsic tunneling junctions in the low temperature range, which is robust even under magnetic field up to 14 T, and thus essentially modifies the classic 1D percolation picture to stabilize a novel quantum percolation state. A new phase diagram is therefore established for the manganite system under quasi-1D confinement for the first time. Our findings offer new insight to understand and manipulate the colorful properties of the electronically phase-separated systems via dimensionality engineering.