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The complex interplay between the lattice geometry and spin–orbit coupling in pyrochlore iridates is shown to give rise to many intriguing phenomena. Here, we report a temperature-dependent Raman scattering study in a series of pyrochlore iridate materials (Y1–xPrx)2Ir2O7which shows magnetic and electronic transition with variation of both temperature as well as composition. Our Raman studies reveal an anomalous change in frequency and line width of F2gand A1gmodes across its transition temperatures while the data in high temperatures mostly follow the anharmonic model. The variation of A1gmode associated with bending vibrations indicates prominent spin-phonon coupling which is mostly induced by a Dzyaloshinskii-Moriya interaction rather than exchange interaction. On the other hand, the signature of electron–phonon interaction is also found to be prominent from stretching F2gmode and opposite line width variation for sample with metallic transition. Thus, our study establishes prominent spin–phonon and electron–phonon coupling and its connection with A-site atoms in pyrochlore iridates.

Field effect transistors (FETs) are considered as the backbone of electronic industry. In this study, we adopted a simple drop cast method for the fabrication of MoS2and WS2channel based FET on commercially available pre-patterned OFET devices. The synthesis of few-layers thick MoS2and WS2nanosheets (NSs) has been done by solvent-assisted exfoliation method. FESEM and TEM study reveals that NSs have lateral dimensions in micron and have polycrystalline nature. From XPS, it is observed that MoS2NSs has 2H phase whereas WS2have hybrid 1T and 2H phase. The frequency difference in Raman vibrational mode for MoS2and WS2NSs is 24.08 cm−1and 63.84 cm−1respectively, confirms that number of layers is reduced after sonication. UV–visible spectroscopy reveals that the bandgap is 1.7 eV and 1.8 eV for MoS2and WS2NSs respectively. Later, these nanosheets have been drop-casted as the channel material on pre-patterned FETs devices and their output and transfer characteristics have been studied. It found that the current On/Off ratio is 104and 103for MoS2and WS2-FET device respectively. This facile fabrication of FET devices may provide a new stage for researchers who do not have access of lithography facilities for FET fabrication.