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arXiv · 2107.00915

Chalcogenide optomemristors for multi-factor neuromorphic computation

Syed Ghazi Sarwat·Timoleon Moraitis·C David Wright·Harish Bhaskaran
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Abstract

Neural processing on devices and circuits is fast becoming a popular approach to emulate biological neural networks. Elaborate CMOS and memristive technologies have been employed to achieve this, including chalcogenide-based in-memory computing concepts. Here we show that nano-scaled films of chalcogenide semiconductors can serve as building-blocks for novel types of neural computations where their tunable electronic and optical properties are jointly exploited. We demonstrate that ultrathin photoactive cavities of Ge-doped Selenide can emulate the computationally powerful non-linear operations of three-factor neo-Hebbian plasticity and the shunting inhibition. We apply this property to solve a maze game through reinforcement learning, as well as a single-neuron solution to the XOR, which is a linearly inseparable problem with point-neurons. Our results point to a new breed of memristors with broad implications for neuromorphic computing.

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Syed Ghazi Sarwat, Timoleon Moraitis, C David Wright, Harish Bhaskaran. 2021-07-02. Chalcogenide optomemristors for multi-factor neuromorphic computation. https://arxiv.org/abs/2107.00915

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