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Abstract Despite superconductor electronics (SCE) advantages, the realization of SCE logic faces a significant challenge due to the absence of dense and scalable nonvolatile memory. While various nonvolatile memory technologies, including Non-destructive readout, vortex transitional memory, and magnetic memory, have been explored, designing a dense crossbar array and achieving a superconductor random-access memory remains challenging. This work introduces a novel, nonvolatile, high-density, and scalable vortex-based memory design for SCE logic called bistable vortex memory. Our proposed design addresses scaling issues with an estimated area of 10 × 10 um2while boasting zero static power with the dynamic energy consumption of 12 aJ for single-bit read and write operations. The current summation capability enables analog operations for in-memory or near-memory computational tasks. We demonstrate the efficacy of our approach with a 32 × 32 superconductor memory array operating at 20 GHz. Additionally, we showcase the accumulation property of the memory through analog simulations conducted on an 8 × 8 superconductor crossbar array.
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A soft, high-density neuroelectronic array
Abstract Techniques to study brain activities have evolved dramatically, yet tremendous challenges remain in acquiring high-throughput electrophysiological recordings minimally invasively. Here, we develop an integrated neuroelectronic array that is filamentary, high-density and flexible. Specifically, with a design of single-transistor multiplexing and current sensing, the total 256 neuroelectrodes achieve only a 2.3 × 0.3 mm2area, unprecedentedly on a flexible substrate. A single-transistor multiplexing acquisition circuit further reduces noise from the electrodes, decreases the footprint of each pixel, and potentially increases the device’s lifetime. The filamentary neuroelectronic array also integrates with a rollable contact pad design, allowing the device to be injected through a syringe, enabling potential minimally invasive array delivery. Successful acute auditory experiments in rats validate the ability of the array to record neural signals with high tone decoding accuracy. Together, these results establish soft, high-density neuroelectronic arrays as promising devices for neuroscience research and clinical applications.
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- Award ID(s):
- 1752274
- PAR ID:
- 10444601
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- npj Flexible Electronics
- Volume:
- 7
- Issue:
- 1
- ISSN:
- 2397-4621
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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