Kumar Virwani

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(165,000 synapses), using phase-change memory as the synaptic weight element G.W.Burr, R.M.Shelby, C.di Nolfo, J.W.Jang‡, R.S.Shenoy, P.Narayanan, K.Virwani, E.U.Giacometti, B.Kurdi, and H.Hwang‡ IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120, Tel: (408) 927–1512, E-mail: gwburr@us.ibm.com ‡Pohang University of Science and Technology,(More)
Mixed-Ionic-Electronic-Conduction (MIEC) at 100% yield G. W. Burr, K. Virwani, R. S. Shenoy, A. Padilla, M. BrightSky†, E. A. Joseph†, M. Lofaro†, A. J. Kellock, R. S. King, K. Nguyen, A. N. Bowers, M. Jurich, C. T. Rettner, B. Jackson, D. S. Bethune, R. M. Shelby, T. Topuria, N. Arellano, P. M. Rice, B. N. Kurdi, and K. Gopalakrishnan IBM Almaden Research(More)
3D crosspoint memory based on Mixed-Ionic-Electronic-Conduction (MIEC) Materials K. Virwani, G. W. Burr, R. S. Shenoy, C. T. Rettner, A. Padilla, T. Topuria, P. M. Rice, G. Ho†, R. S. King, K. Nguyen, A. N. Bowers, M. Jurich, M. BrightSky†, E. A. Joseph†, A. J. Kellock, N. Arellano, B. N. Kurdi and K. Gopalakrishnan† IBM Almaden Research Center, 650 Harry(More)
Magnetic nanoparticles (MNPs) provide a set of building blocks for constructing stimuli-responsive nanoscale materials with properties that are unique to this scale. The size and the composition of MNPs are tunable to meet the requirements for a range of applications including biosensors and data storage. Although many of these technologies would(More)
Nitrogen-based thermoset polymers have many industrial applications (for example, in composites), but are difficult to recycle or rework. We report a simple one-pot, low-temperature polycondensation between paraformaldehyde and 4,4'-oxydianiline (ODA) that forms hemiaminal dynamic covalent networks (HDCNs), which can further cyclize at high temperatures,(More)
The emergence of new nonvolatile memory (NVM) technologies—such as phase change memory, resistive, and spin-torque-transfer magnetic RAM—has been motivated by exciting applications such as storage class memory, embedded nonvolatile memory, enhanced solid-state disks, and neuromorphic computing. Many of these applications call for such NVM devices to be(More)
We demonstrate compact integrated arrays of BEOL-friendly novel access devices (AD) based on Cu-containing MIEC materi-als[1-3]. In addition to the high current densities and large ON/OFF ratios needed for Phase Change Memory (PCM), scaled-down ADs also exhibit larger voltage margin Vm, ultra-low leakage (<10pA), and much higher endurance (>10 8) at high(More)
A self-assembled magnetic recording medium was created using colloidal ferrimagnetic building blocks. Monodisperse cobalt ferrite nanoparticles (CoFe(2)O(4)) were synthesized using solution-based methods and then stabilized in solution using the amphiphilic diblock copolymer, poly(acrylic acid)-b-poly(styrene) (PAA-PS). The acid groups of the acrylate block(More)
A cantilever type has been developed for dynamic force microscopy by the addition of a harmonic oscillator in the form of a paddle to atomic force microscopy cantilevers. These cantilevers provide resonant amplification of periodic interactions between the probe and the substrate when the laser is aligned on the paddle. The cantilevers were explored for(More)
Phase change memory (PCM) could potentially achieve high density with large, 3D-stacked crosspoint arrays, but not without a BEOL-friendly access device (AD) that can provide high current densities and large ON/OFF ratios. We demonstrate a novel AD based on Cu-ion motion in novel Cu-containing Mixed Ionic Electronic Conduction (MIEC) materials[1, 2].(More)