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The synchronization of complex networks, as an important and captivating dynamic phenomenon, has been investigated across diverse domains ranging from social activities to ecosystems and power systems. Furthermore, the synchronization of networks proves instrumental in solving engineering quandaries, such as cryptography and image encryption. And finite-time synchronization (FTS) controls exhibit substantial resistance to interference, accelerating network convergence speed and heightening control efficiency. In this paper, finite-time synchronization (FTS) is investigated for a class of fractional-order nonidentical complex networks under uncertain parameters (FONCNUPs). Firstly, some new FTS criteria for FONCNUPs are proposed based on Lyapunov theory and fractional calculus theory. Then, the new controller is designed based on inequality theory. Compared to the general controller, it controls all nodes and adds additional control to some of them. When compared to other controllers, it has lower control costs and higher efficiency. Finally, a numerical example is presented to validate the effectiveness and rationality of the obtained results. [ABSTRACT FROM AUTHOR]

In this paper, the fixed-time multi-switch combination–combination synchronization (FTMSCCS) of fractional-order chaotic systems with uncertainties and external disturbances is studied. The appropriate sliding mode surface and controller are proposed based on a Lyapunov theorem, and fixed-time multi-switching combination–combination synchronizations between four fractional-order chaotic systems are realized. The Lyapunov function is designed to prove the feasibility of the controller theoretically, and the effectiveness and robustness of the synchronization mechanism are further verified by numerical simulations. The advantage of this article is that it extends fixed-time synchronization to multi-switch combination–combination synchronization, enabling synchronization for a limited time, while increasing the complexity of the synchronization mechanism and improving its confidentiality in communication applications. [ABSTRACT FROM AUTHOR]

Nonepitaxially grown Ba0.6 Sr0.4 TiO3 ( NE- BSTO) thin film with tunability of 65.4% and low leakage current was obtained on Ir electrode by oxygen plasma-assisted pulsed laser deposition ( PLD), and epitaxially grown Ba0.6 Sr0.4 TiO3 (E- BSTO) thin film with tunability of 32.5% was obtained by PLD without plasma assistance. Results indicate that the NE- BSTO film possessed higher oxygen content, lower tetragonal distortion, and low stress, all of which contributed to its excellent dielectric properties. This work demonstrates that NE- BSTO thin films are well suited for room temperature tunable microwave device applications. [ABSTRACT FROM AUTHOR]

A doping mode and its mechanism are proposed for Fe3+/Fe2+-doped (Ba,Sr)TiO3 thin films of the perovskite structure (ABO3), in which the substitutions of Fe3+/Fe2+ for the B site are coexisting to match the lattice distortion and release the strain energy, which is kind of like “domain matching”. Experimental results indicated that Fe dopant had little effect on the epitaxial growth of Ba0.6Sr0.4TiO3 thin films, but had much effect on the suppression of defects such as oxygen vacancies, and the reduction of the leakage current density. With different Fe dopants, the Poole-Frenkel emission, the Schottky junction and the ohmic-like contact separately dominated the leakage current in different voltage regions. [ABSTRACT FROM AUTHOR]