Parameter optimization for transitions between memory states in small arrays of Josephson junctions
Abstract
Coupled arrays of Josephson junctions possess multiple stable zero voltage states. Such states can store information and consequently can be utilized for cryogenic memory applications. Basic memory operations can be implemented by sending a pulse to one of the junctions and studying transitions between the states. In order to be suitable for memory operations, such transitions between the states have to be fast and energy efficient. Here in this article we employed simulated annealing, a stochastic optimization algorithm, to study parameter optimization of array parameters which minimizes times and energies of transitions between specifically chosen states that can be utilized for memory operations (Read, Write, and Reset). Simulation results show that such transitions occur with access times on the order of 10–100 ps and access energies on the order of 10 ^{19}–5×10 ^{18} J. Numerical simulations are validated with approximate analytical results.
 Authors:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computer Science and Mathematics Division; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computing and Computational Sciences Directorate; Univ. of Delaware, Newark, DE (United States). Dept. of Mathematical Sciences
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computing and Computational Sciences Directorate
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computer Science and Mathematics Division; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computing and Computational Sciences Directorate; ; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical, Aerospace, and Biomedical Engineering
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1407744
 DOE Contract Number:
 AC0500OR22725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physica. A; Journal Volume: 474; Journal Issue: C
 Country of Publication:
 United States
 Language:
 English
 Subject:
 97 MATHEMATICS AND COMPUTING; Josephson junction; Memory cell; Parameter optimization; Nonlinear dynamical systems
Citation Formats
Rezac, Jacob D., Imam, Neena, and Braiman, Yehuda. Parameter optimization for transitions between memory states in small arrays of Josephson junctions. United States: N. p., 2017.
Web. doi:10.1016/j.physa.2017.01.044.
Rezac, Jacob D., Imam, Neena, & Braiman, Yehuda. Parameter optimization for transitions between memory states in small arrays of Josephson junctions. United States. doi:10.1016/j.physa.2017.01.044.
Rezac, Jacob D., Imam, Neena, and Braiman, Yehuda. Wed .
"Parameter optimization for transitions between memory states in small arrays of Josephson junctions". United States.
doi:10.1016/j.physa.2017.01.044.
@article{osti_1407744,
title = {Parameter optimization for transitions between memory states in small arrays of Josephson junctions},
author = {Rezac, Jacob D. and Imam, Neena and Braiman, Yehuda},
abstractNote = {Coupled arrays of Josephson junctions possess multiple stable zero voltage states. Such states can store information and consequently can be utilized for cryogenic memory applications. Basic memory operations can be implemented by sending a pulse to one of the junctions and studying transitions between the states. In order to be suitable for memory operations, such transitions between the states have to be fast and energy efficient. Here in this article we employed simulated annealing, a stochastic optimization algorithm, to study parameter optimization of array parameters which minimizes times and energies of transitions between specifically chosen states that can be utilized for memory operations (Read, Write, and Reset). Simulation results show that such transitions occur with access times on the order of 10–100 ps and access energies on the order of 1019–5×1018 J. Numerical simulations are validated with approximate analytical results.},
doi = {10.1016/j.physa.2017.01.044},
journal = {Physica. A},
number = C,
volume = 474,
place = {United States},
year = {Wed Jan 11 00:00:00 EST 2017},
month = {Wed Jan 11 00:00:00 EST 2017}
}

Here, we study memory states of a circuit consisting of a small inductively coupled Josephson junction array and introduce basic (write, read, and reset) memory operations logics of the circuit. The presented memory operation paradigm is fundamentally different from conventional single quantum flux operation logics. We calculate stability diagrams of the zerovoltage states and outline memory states of the circuit. We also calculate access times and access energies for basic memory operations.

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