Atomistic Origins of Conductance Switching in an ε-Cu0.9V2O5 Neuromorphic Single Crystal Oscillator

作者：John D. Ponis, Nicholas Jerla, George Agbeworvi, Saul Perez-Beltran, Nitin Kumar, Kenna Ashen, Jialu Li, Edrick Wang, Michelle A. Smeaton, Fatme Jardali, S. Chakraborty, Patrick J. Shamberger, Katherine Jungjohann, Conan Weiland, Cherno Jaye, Lu‐Fang Ma, Daniel A. Fischer, Jinghua Guo, G. Sambandamurthy, Xiaofeng Qian, Sarbajit Banerjee · 发表于：Journal of the American Chemical Society · 年份：2024 · DOI：10.1021/jacs.4c11968 · 被引用次数：5 · 研究领域：Advanced Memory and Neural Computing、Transition Metal Oxide Nanomaterials、Electronic and Structural Properties of Oxides

High Resolution Image Download MS PowerPoint Slide Building artificial neurons and synapses is key to achieving the promise of energy efficiency and acceleration envisioned for brain-inspired information processing. Emulating the spiking behavior of biological neurons in physical materials requires precise programming of conductance nonlinearities. Strong correlated solid-state compounds exhibit pronounced nonlinearities such as metal–insulator transitions arising from dynamic electron–electron and electron–lattice interactions. However, a detailed understanding of atomic rearrangements and their implications for electronic structure remains obscure. In this work, we unveil discontinuous conductance switching from an antiferromagnetic insulator to a paramagnetic metal in ε-Cu 0.9 V 2 O 5 . Distinctively, fashioning nonlinear dynamical oscillators from entire millimeter-sized crystals allows us to map the structural transformations underpinning conductance switching at an atomistic scale using single-crystal X-ray diffraction. We observe superlattice ordering of Cu ions between [V 4 O 10 ] layers at low temperatures, a direct result of interchain Cu-ion migration and intrachain reorganization. The resulting charge and spin ordering along the vanadium oxide framework stabilizes an insulating state. Using X-ray absorption and emission spectroscopies, assigned with the aid of electronic structure calculations and measurements of partially and completely decuprated samples, we fin...