Work

Pressure-induced hole delocalization in the strongly correlated quasicubic charge-transfer perovskite LaBa 2 Fe 3 O 8 + δ

Year: 2025

Type: article

Abstract: Analysis of the thermal and baric evolution of resistance in ${\mathrm{LaBa}}_{2}{\mathrm{Fe}}_{3}{\mathrm{O}}_{8+\ensuremath{\delta}}$ enabled the construction of its pressure-temperature (P-T) phase diagram, which prominently displays a critical boundary, ${P}_{c}^{\mathrm{MIT}}(T)$, marking the transition from localized to hole-type extended states. The relatively low critical pressures $[{P}_{c}^{\mathrm{MIT}}(T)\ensuremath{\approx}3--8\phantom{\rule{0.16em}{0ex}}\text{GPa}]$ suggest that, as $P\ensuremath{\rightarrow}{P}_{c}$ in this narrow-gap, strongly correlated charge-transfer system, both the hybridization strength and the charge-transfer character are progressively enhanced, ultimately leading to the emergence of metallicity. Emphasizing the electronic nature of this transition, pressure-dependent structural analyses at room temperature reveal no associated structural phase transition at ${P}_{c}^{\mathrm{MIT}}(T)$; the system retains a (weakly tetragonally distorted) quasicubic perovskite structure with Murnaghan-type compressibility up to 30 GPa. The emergence of hole delocalization and metallic conduction, coupled with suppressed antiferromagnetism, suggests proximity to quantum criticality.

Source: Physical review. B./Physical review. B

DOI: 10.1103/9f77-47x3

Authors: M. ElMassalami, S. Favre, M. B. Silva Neto

Institutions: Universidade Federal do Rio de Janeiro, Universidad de la República de Uruguay

Language: English

Topic: Magnetic and transport properties of perovskites and related materials

Subfield: Electronic, Optical and Magnetic Materials

Field: Materials Science

Domain: Physical Sciences

Open Access status: green

Funder: Laboratório Nacional de Luz Síncrotron

Award: G1516714385