The coupling of electronic degrees of freedom in materials to create "hybridized functionalities" is a holy grail of modern condensed matter physics that may produce versatile mechanisms of control. Correlated electron systems often exhibit coupled degrees of freedom with a high degree of tunability which sometimes lead to hybridized functionalities based on external stimuli. However, the mechanisms of tunability and the sensitivity to external stimuli are determined by intrinsic material properties which are not always controllable. A Mott metalinsulator transition (MIT) is technologically attractive due to the large changes in resistance, tunable by doping, strain, electric fields, and orbital occupancy but not, in and of itself, controllable with light. Here, an alternate approach is presented to produce optical functionalities using a properly engineered photoconductor/strongly correlated hybrid heterostructure. This approach combines a photoconductor, which does not exhibit an MIT, with a strongly correlated oxide, which is not photoconducting. Due to the intimate proximity between the two materials, the heterostructure exhibits giant volatile and nonvolatile, photoinduced resistivity changes with substantial shifts in the MIT transition temperatures. This approach can be extended to other judicious combinations of strongly correlated materials.

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Synchronization of electrical oscillators is a crucial step toward practical implementation of oscillator-based and bio-inspired computing. Here, we report the emergence of an unusual stochastic pattern in coupled spiking Mott nanodevices. Although a moderate capacitive coupling results in a deterministic alternating spiking, increasing the coupling strength leads counterintuitively to stochastic disruptions of the alternating spiking sequence. The disruptions of the deterministic spiking sequence are a direct consequence of the small intrinsic stochasticity in electrical triggering of the insulator–metal transition. Although the stochasticity is subtle in individual nanodevices, it becomes dramatically enhanced just in a single pair of coupled oscillators and, thus, dominates the synchronization. This is different from the stochasticity and multimodal coupling, appearing due to collective effects in large oscillator networks. The stochastic spiking pattern in Mott nanodevices results in a discrete inter-spike interval distribution resembling those in biological neurons. Our results advance the understanding of the emergent synchronization properties in spiking oscillators and provide a platform for hardware-level implementation of probabilistic computing and biologically plausible electronic devices.

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