Tunable Spin Correlated‐Plasmons Ranging from Infrared to Ultraviolet in Pr0.6Sr0.4Co1−xMnxO3

Abstract

Herein, new spin correlated‐plasmons in Pr0.6Sr0.4Co1−xMnxO3 (x = 0–0.4) that are tunable and stable at room temperature are demonstrated. Using advanced spectroscopic techniques, the charge, spin, and orbital interaction that triggers the spin correlated‐plasmons in spin‐polarized Co4+, O2−, and Mn4+ is identified. As a function of x, Co4+ systematically changes the spin state of the spin correlated‐plasmons (from high, intermediate, to low spin), which also sequentially transforms the metallic cobaltite into a Mott insulator. Spin correlated‐plasmons in the IR range, being excited from Co4+, tend to dominate in the metallic phase of the cobaltites, whereas Mn4+ and O2− are the primary source for the spin correlated‐plasmons in the UV–vis ranges in the insulating phase.