arXiv subjects

Uday S. Goteti

Publications and source records attributed to Uday S. Goteti.

5 recordsLinked to original sources

arXiv2026

Information dynamics of our brains in dynamically driven disordered superconducting loop networks

Complex systems of many interacting components exhibit patterns of recurrence and emergent behaviors in their time evolution that can be understood from a new perspective of physics of information dynamics, modeled after one such system, our brains. A generic brain-like network model is derived from a system of disordered superconducting loops with Josephson junction oscillators to demonstrate these behaviors. The loops can trap multiples of fluxons that represent quantized information units in many distinct memory configurations populating a state space. The state can be updated by exciting the junctions to allow the movement of fluxons through the network as the current through them surpasses their thresholds. Numerical simulations performed with a lumped circuit model of a 4-loop network show that information written through excitations is translated into stable states of trapped flux and their time evolution. Experimental implementation on the 4-loop network shows dynamically stable flux flow in each pathway characterized by the junction firing statistics. The network separates information from multiple excitations into state categories with large energy barriers observed in simulations that correspond to different flux (information) flow patterns observed across junctions in experiments. Strong evidence for associative and time-dependent (short-to-long-term) memories distributed across the network is observed, dependent on its intrinsic and geometrical properties as described by the model. Loop network topology abstraction using the model separates the flowing patterns of information from its physical constraints and describes systems of any scale and complexity. The accuracy of flow statistics are limited by the resolution of local external measuring clock(s) revealing the universal nature of information dynamics through the stated two principles.

cond-mat.dis-nn↗

arXiv2021

Low-temperature emergent neuromorphic networks with correlated oxide devices

Neuromorphic computing which aims to mimic the collective and emergent behavior of the brain's neurons, synapses, axons, dendrites offers an intriguing, potentially disruptive solution to society's ever-growing computational needs. Although much progress has been made in designing circuit elements that mimic the behavior of neurons and synapses, challenges remain in designing networks of elements that feature a collective response behavior. We present simulations of networks of circuits and devices based on superconducting and Mott-insulating oxides that display a multiplicity of emergent states that depend on the spatial configuration of the network. Our proposed network designs are based on experimentally known ways of tuning the properties of these oxides using light ions. We show how neuronal and synaptic behavior can be achieved with arrays of superconducting Josephson junction loops, all within the same device. We also show how a multiplicity of synaptic states could be achieved by designing arrays of devices based on hydrogenated rare-earth nickelates. Together, our results demonstrate a new research platform that utilizes the collective macroscopic properties of quantum materials to mimic the emergent behavior found in biological systems.

physics.app-ph↗

arXiv2019

Complementary Quantum Logic Family Using Josephson Junctions and Quantum Phase-Slip Junctions

In this article, we explore a new set of circuits, that incorporate both single-flux-quantum and quantized charge-based complementary quantum logic circuits. Circuits that convert single-flux-quantum voltage pulses to quantized charge pulses and vice versa are introduced that lead to circuits that simplify logic and integration operations of individual flux and charge based logic circuits. These include fan-out circuits that enable single flux input to several charge outputs and control gate circuit with charge input controlling flux output. The operation of these circuits is demonstrated in simulations using WRSPICE. An XOR gate implementation is presented as an example to illustrate the operation of these circuits. The developed complementary quantum logic circuits show promise for higher power efficiency and simpler design in the form of fewer junctions for a given logic implementation, leading to the possibility of higher integration density.

physics.app-ph↗

arXiv2018

Superconducting Neuromorphic Computing Using Quantum Phase-Slip Junctions

Superconducting circuits based on quantum phase-slip junctions (QPSJs) can conduct quantized charge pulses, which naturally resemble action potentials generated by biological neurons. A corresponding synaptic circuit, which works as a weighted connection between two neurons, can also be realized by circuits comprised of QPSJs and magnetic Josephson junctions (MJJs) as a means of charge modulation for quantized charge propagation. In this paper, we present basic neuromorphic components such as neuron and synaptic circuits based on superconducting QPSJs and MJJs. Using a SPICE model developed for QPSJs, neuron and synaptic circuits have been simulated in WRSPICE to demonstrate possible operation. We provide estimates for QPSJ energy dissipation and operation speed based on calculations using simple models. The challenges for implementation of this technology are also briefly discussed.

cs.ET↗

arXiv2018

Charge-based superconducting digital logic family using quantum phase-slip junctions

Superconducting digital computing systems, primarily involving Josephson junctions are actively being pursued as high performance and low energy dissipating alternatives to CMOS-based technologies for petascale and exascale computers, although several challenges still exist in overcoming barriers to practically implement these technologies. In this paper, we present an alternative superconducting logic structure: quantized charge-based logic circuits using quantum phase-slip junctions, which have been identified as dual devices to Josephson junctions. Basic principles of logic implementation using quantum phase-slips are presented in simulations with the help of a SPICE model that has been developed for the quantum phase-slip structures. Circuit elements that form the building blocks for complex logic circuit design are introduced. Two different logic gate designs: OR gate and XOR gate are presented to demonstrate the usage of the building blocks introduced.

physics.app-ph↗