Electronic properties of materials with strong electronic correlations: spectroscopy and ab-initio calculations

Materials with strong electronic correlations have many functional properties (insulator-metal transition, magnetoresistance, superconductivity, high dielectric constant, …) that remain however poorly understood. MAGNETOPICS team uses both Raman scattering and optical spectroscopy (far-infrared to UV) to investigate vibrational and electronic properties of materials. Our experimental facilities allow measurements of microscopic samples under extreme conditions (very high pressure and low/high temperature).
In order to get a better insight of properties, our experimental results are usually supplemented by ab-initio calculations.

We are interested in various family of materials such as oxides, chalcogenides, organic compounds, for applications in the fields of R-RAMs, flexible electronics, neural networks, sensors, solar cells, energy storage, …
 

Recent work

Polarized Raman scattering on single crystals of rare earth orthochromite RCrO3 (R = La, Pr, Nd, and Sm)

 

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Polarized Raman scattering on orthorhombic RCrO3 (R = La, Pr, Nd, and Sm) single crystals was measured at room temperature. Phonon frequency evolutions as a function of orthorhombic distortion were investigated and highlighted a complex behavior for several modes. phonon modes were unambiguously assigned on the basis of both Raman selection rules and lattice dynamics calculations within density functional perturbations theory.






 

Interplay between bandwidth-controlled and filling-controlled pressure-induced Mott insulator to metal transition in the molecular compound [Au(Et-thiazdt)2]

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We performed optical conductivity measurements under high pressure and Density Functionnal Theory calculations
to study the Mott transition in the single-component organic conductor [Au(Et-thiazdt)2].