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DOE OSTI · 3378003

Multifunctional electrochemical memory stabilized by phase coexistence

Oh, Sangheon [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0000000323717410)·Gross, Adam L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0000000197691183)·Christensen, Adam Scott [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000168729998)·Zhu, Jacklyn [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0009000307712158)·Finnegan, Patrick Sean [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000241166379)·Sugar, Joshua Daniel [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0009000245752807)·Bishop, Sean Robert [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000213331859)·Gilbert, Simeon James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000304029305)·Williams, R. Stanley [Texas A & M Univ., College Station, TX (United States); Univ. of Southern California, Los Angeles, CA (United States)] (ORCID:0000000302134259)·Balbuena, Perla B. [Texas A & M Univ., College Station, TX (United States)] (ORCID:0000000223583910)·Woo, Kyung Seok [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Ulsan National Institute of Science and Technology (UNIST), Ulsan (Korea, Republic of)] (ORCID:0000000191847255)·Brown, Timothy D. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Oklahoma State Univ., Stillwater, OK (United States)] (ORCID:0000000347068355)·Fuller, Elliot James [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0000000179128688)·Kumar, Suhas [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Rain AI, San Francisco, CA (United States); Nanyang Technological Univ. (Singapore)] (ORCID:0000000267727250)·Talin, Albert Alec [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:000000021102680X)
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Abstract

Our growing computing needs, especially in applications that heavily rely on artificial intelligence (AI), motivate a search for new components that could substantially augment the performance of general-purpose digital computers. Beyond ON/OFF switching, new components with linear multistate analog resistive tuning, nonlinear volatile switching, spiking, oscillatory, stochastic and other complex functionalities could enable highly efficient neuromorphic computing schemes for AI information processing. Compared to the extreme multifunctionality of biological neurons, realizing all the above characteristics in a single, scalable analog component remains a grand challenge. Here we investigate electrochemical gating combined with localized thermal activation to program and switch a single, vertically integrated and dimensionally scaled electrothermal chemical random access memory (ETCRAM) with a channel and reservoir composed of phase-separated vanadium oxide. Closely related to electrochemical RAM (ECRAM), ETCRAM uses an integrated gate-heater electrode to overcome kinetic barriers that help retain states at ambient temperatures. In addition to synapse-like stable and programmable analog resistance states arising from redox-tunable phase coexistence, a single component exhibits neuron-like nonlinear conductance switching with a tunable threshold and self-driven dynamics owing to the thermally driven metal-insulator phase transition in vanadium dioxide. More broadly, we demonstrate that electrochemically stabilized phase coexistence could unlock analog electronics with novel functionality, stability, reconfigurability, and scalability.

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BibTeXRIS

Oh, Sangheon [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0000000323717410), Gross, Adam L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0000000197691183), Christensen, Adam Scott [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000168729998), Zhu, Jacklyn [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0009000307712158), Finnegan, Patrick Sean [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000241166379), Sugar, Joshua Daniel [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0009000245752807), Bishop, Sean Robert [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000213331859), Gilbert, Simeon James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000304029305), Williams, R. Stanley [Texas A & M Univ., College Station, TX (United States); Univ. of Southern California, Los Angeles, CA (United States)] (ORCID:0000000302134259), Balbuena, Perla B. [Texas A & M Univ., College Station, TX (United States)] (ORCID:0000000223583910), Woo, Kyung Seok [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Ulsan National Institute of Science and Technology (UNIST), Ulsan (Korea, Republic of)] (ORCID:0000000191847255), Brown, Timothy D. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Oklahoma State Univ., Stillwater, OK (United States)] (ORCID:0000000347068355), Fuller, Elliot James [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:0000000179128688), Kumar, Suhas [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Rain AI, San Francisco, CA (United States); Nanyang Technological Univ. (Singapore)] (ORCID:0000000267727250), Talin, Albert Alec [Sandia National Lab. (SNL-CA), Livermore, CA (United States)] (ORCID:000000021102680X). 2026-07-10. Multifunctional electrochemical memory stabilized by phase coexistence. https://doi.org/10.1126/sciadv.aee1908

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