Future‐generation neuromorphic computing seeks to overcome the limitations of von Neumann architectures by colocating logic and memory functions, thereby emulating the function of neurons and synapses in the human brain. Despite remarkable demonstrations of high‐fidelity neuronal emulation, the predictive design of neuromorphic circuits starting from knowledge of material transformations remains challenging. VO2 is an attractive candidate since it manifests a near‐room‐temperature, discontinuous, and hysteretic metal–insulator transition. The transition provides a nonlinear dynamical response to input signals, as needed to construct neuronal circuit elements. Strategies for tuning the transformation characteristics of VO2 based on modification of material properties, interfacial structure, and field couplings, are discussed. Dynamical modulation of transformation characteristics through in situ processing is discussed as a means of imbuing synaptic function. Mechanistic understanding of site‐selective modification; external, epitaxial, and chemical strain; defect dynamics; and interfacial field coupling in modifying local atomistic structure, the implications therein for electronic structure, and ultimately, the tuning of transformation characteristics, is emphasized. Opportunities are highlighted for inverse design and for using design principles related to thermodynamics and kinetics of electronic transitions learned from VO2 to inform the design of new Mott materials, as well as to go beyond energy‐efficient computation to manifest intelligence.

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The development of electrical insulators that are thermally conducting is critical for thermal management applications in many advanced electronics and electrical devices. Here, we synthesized polymer nanocomposite (PNC) films composed of polymers [polyethylenimine, poly(vinylamine), poly(acrylic acid), and poly(ethylene oxide)] and dielectric fillers (montmorillonite clay and hexagonal boron nitride) by layer-by-layer technique. The cross-plane thermal conductivity [Formula: see text] of the film was measured by the 3ω method. The effect of various factors such as film growth, filler type, filler volume fraction, polymer chemical structures, and temperature on the thermal conductivity is reported. The [Formula: see text] of PNCs with thickness from 37 nm to 1.34  μm was found to be in the range of 0.11 to 0.21 ± 0.02 W m−1 K−1. The [Formula: see text] values were found to be lower than the constituent polymer matrix. The experimental result is compared with existing theoretical models of nanocomposite systems to get insight into heat transfer behavior in such layered films composed of dielectrics and polymers.

The characteristic metal–insulator phase transition (MIT) in vanadium dioxide results in nonlinear electrical transport behavior, allowing VO2 devices to imitate the complex functions of neurological behavior. Chemical doping is an established method for varying the properties of the MIT, and interstitial dopant boron has been shown to generate a unique dynamic relaxation effect in individual B‐VO2 particles. This paper describes the first demonstration of an electrically stimulated B‐VO2 proto‐device which manifests a time‐dependent critical transformation temperature and switching voltage derived from the coupling of dopant diffusion dynamics and the metal–insulator transition of VO2. During quasi‐steady current‐driven transitions, the electrical responses of B‐VO2 proto‐devices show a step‐by‐step progression through the phase transformation, evidencing domain transformations within individual particles. The dynamic relaxation effect is shown to increase the critical switching voltage by up to 41% (ΔVcrit = 0.13 V) and also to increase the resistivity of the M1 phase of B‐VO2 by 14%, imbuing a memristive response derived from intrinsic material properties. These observations demonstrate the dynamic relaxation effect in B‐VO2 proto‐devices whose electrical transport responses can be adjusted by electronic phase transitions triggered by temperature but also by time as a result of intrinsic dynamics of interstitial dopants.

Negative differential resistance (NDR) in certain materials has been attributed to spontaneous emergence of symmetry‐breaking electrical current density localization from a previously homogeneous distribution, which is postulated to occur due to the nonequilibrium thermodynamic force of minimization of entropy production. However, this phenomenon has not been quantitatively predicted based on intrinsic material properties and an applied electrical stimulus. Herein an instability criterion is derived for localization of current density and temperature from a thermal fluctuation in a parallel conductor model of a thin film that is subject to Newton's law of cooling. The conditions for steady–state electro‐thermal localization is predicted, verifying a decrease in entropy production upon localization. Electro‐thermal localization accompanied by a decrease of entropy production is confirmed in a multiphysics simulation of current flow in a thin film. The instability criterion predicts conditions for spontaneous current density localization, relating symmetry breaking fundamentally to dynamical instability via Local Activity theory.