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Vanadium oxides are known for their metal–insulator transition (MIT), with V3O5 being notable for its transition temperature exceeding room temperature. At about 430 K, this material shows a change in crystal symmetry accompanied with one order of magnitude increase in its electrical conductivity and alterations in its optical properties. Although the property changes during the MIT in V3O5 are less pronounced than those observed in VO2, its transition temperature is 90 K higher, making it appealing for applications requiring elevated temperatures. In this article, the high-frequency characteristics were determined in a V3O5 two-terminal device in the range from 5 to 35 GHz. The S-parameters showed that the return loss at room temperature was close to −1.5 dB, and the isolation between ports was approximately −50 dB. At temperatures above the metal–insulator transition, the isolation decreased to around −40 dB at 35 GHz. For S11 and S22, similar behavior was observed at room temperature, with a notable change in the S-parameter phase of the device. This behavior suggests that V3O5 may function well as a capacitor because the considerable change in phase could control the flow of electrical signals in devices. This property also may be used for matching purposes, especially considering its response to temperature changes. Additionally, conductivity calculation from S-parameters shows a decrease of approximately two orders of magnitude at 500 K and one order of magnitude at 300 K compared to DC values. These findings highlight V3O5 potential for integration into radio frequency devices that demand consistent performance in high-temperature environments. 

Femtosecond spectroscopy of FeSe film shows distinct transient nematic behavior below and above superconducting critical temperature. Results reveal correlations between photoinduced nematicity, quasiparticle formation, superconducting and pseudogap openings, emphasizing electronic correlations and preformed electron pairing. 

Time-resolved ultrafast reflectivity measurements along with the two-temperature model analysis reveal a complex interplay between optical nonlinearities, structural phase transition, electronic correlations, electron-phonon energy transfer, and the second moment of Eliashberg function in FeSe_0.8Te_0.2. 

Vanadium oxide V3O5 exhibits an insulator-to-metal transition (IMT) near 430 K, which is the highest value for all vanadium oxides exhibiting IMTs. This makes it interesting for advanced electronic applications. However, the properties of V3O5 have been little studied, and, in particular, there are no reports of experimentally determined mechanical properties. In this work, Young’s modulus of sputter-deposited V3O5 thin films has been determined by measuring the fundamental resonant frequency of V3O5-coated silicon microcantilevers using a laser beam deflection technique. After deposition, the films were characterized by x-ray diffraction, resistivity measurements, and atomic force microscopy. The value of Young’s modulus experimentally determined for V3O5 was 198 ± 14 GPa, which is slightly lower than the computationally derived values for bulk crystal V3O5. 

Femtosecond photoexcitation of Ba(Fe_0.92Co_0.08)₂As₂superconductors reveals distinct dynamics of laser fluence-dependent ultrafast processes. The modified two-temperature model shows the complex interplay between thermalization time constants, electron-phonon coupling parameters, and level of optical excitation.