Multi-messenger nanoprobes of hidden magnetism in a strained manganite

• Published in: Nature materials 2020-04, Vol.19 (4), p.397-404
• Main Authors: McLeod, A. S., Zhang, Jingdi, Gu, M. Q., Jin, F., Zhang, G., Post, K. W., Zhao, X. G., Millis, A. J., Wu, W. B., Rondinelli, J. M., Averitt, R. D., Basov, D. N.
• Format: Article
• Language: English
• Subjects: 639/301/119/2793; 639/301/119/2795; 639/301/119/544; 639/301/119/995; 639/301/119/997; Antiferromagnetism; Atomic force microscopy; Biomaterials; Chemistry and Materials Science; Condensed Matter Physics; Ferromagnetic materials; First principles; Functional materials; Jahn-Teller effect; Light microscopy; Magnetic fields; Magnetic properties; Magnetism; Materials Science; Microscopes; Microscopy; Nanotechnology; Near fields; Optical and Electronic Materials; Optical microscopy; optics, defects, charge transport, superconductivity, magnetism and spin physics, mesoscale science, materials and chemistry by design, mesostructured materials, synthesis (novel materials), synthesis (self-assembly); Ultrafast lasers
• ISSN: 1476-1122; 1476-4660
• DOI: 10.1038/s41563-019-0533-y

The ground-state properties of correlated electron systems can be extraordinarily sensitive to external stimuli, offering abundant platforms for functional materials. Using the multi-messenger combination of atomic force microscopy, cryogenic scanning near-field optical microscopy, magnetic force microscopy and ultrafast laser excitation, we demonstrate both ‘writing’ and ‘erasing’ of a metastable ferromagnetic metal phase in strained films of La 2/3 Ca 1/3 MnO 3 (LCMO) with nanometre-resolved finesse. By tracking both optical conductivity and magnetism at the nanoscale, we reveal how strain-coupling underlies the dynamic growth, spontaneous nanotexture and first-order melting transition of this hidden photoinduced metal. Our first-principles calculations reveal that epitaxially engineered Jahn–Teller distortion can stabilize nearly degenerate antiferromagnetic insulator and ferromagnetic metal phases. We propose a Ginzburg–Landau description to rationalize the co-active interplay of strain, lattice distortions and magnetism nano-resolved here in strained LCMO, thus guiding future functional engineering of epitaxial oxides into the regime of phase-programmable materials. A multi-messenger combination of atomic force microscopy, scanning near-field optical microscopy and magnetic force microscopy demonstrates a strain-modulated photoinduced ferromagnetic metallic state in La 2/3 Ca 1/3 MnO 3 .