The possibility of a new design concept for dual spin crossover based sensors for concomitant detection of both temperature and pressure is presented. It is conjectured from numerical results obtained by mean field approximation applied to a Ising-like model that using two different spin crossover compounds containing switching molecules with weak elastic interactions it is possible to simultaneously measure P and T. When the interaction parameters are optimized, the spin transition is gradual and for each spin crossover compounds, both temperature and pressure values being identified from their optical densities. This concept offers great perspectives for smart sensing devices.

Direct current (dc) electrical transport properties (resistivity and Hall) and spectroscopic ellipsometric measurements have been combined to study high-quality epitaxial thin films of ${\text{LaNiO}}_3$ (LNO) on ${\text{SrTiO}}_3$ (001) substrates. Stoichiometry of ${\text{LaNiO}}_3$ films was changed by varying the oxygen partial pressure between 240 and $420\mu \text{bar}$ during the growth in a pulsed laser deposition setup. Structural and temperature-dependent transport properties conform to epitaxial ${\text{LaNiO}}_3$ . The ellipsometric data, measured in the 350–850 nm spectral range, are adjusted with a dispersion relation of Drude-Lorentz (DL) type. In addition to the Drude term, only one Lorentz oscillator was used in the modeling for consistency with existing density of states calculations. Increasing oxygen pressure does not induce significant variations of the electronic density, the Hall mobility, or the Drude plasma energy. Neither are the pseudo-cubic lattice parameter and the Lorentz oscillator resonance energy significantly modified. Resistivity from dc transport and “optical” resistivity from the DL dispersion relation are found to be in good agreement in the case of epitaxial LNO films, giving an elegant way to control the electrical properties of the ${\text{LaNiO}}_3$ conductive oxide thin films in situ by the spectroscopic ellipsometry technique during growth.