The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Jonathan A. Malen - One of the best experts on this subject based on the ideXlab platform.
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Nondiffusive Thermal Transport Increases Temperature Rise in RRAM Filaments
IEEE Electron Device Letters, 2016Co-Authors: Keith T. Regner, Jonathan A. MalenAbstract:Thermal transport in resistive random-access memory (RRAM) is modeled in the set state, where the conductive filament (CF) is approximated by an infinitely long cylinder embedded in crystalline rutile TiO2, a prototypical RRAM material. Determination of the phonon mean free path (MFP) spectrum in TiO2 shows that MFPs are similar to the CF radius, indicating that thermal transport is nondiffusive. We develop an analytical solution to the Boltzmann transport Equation (BTE) to model the nondiffusive thermal transport in TiO2 and find that the surface temperature rise of the CF predicted by the BTE is larger than that predicted by the Heat Diffusion Equation (e.g., $4\times $ larger for a 1 nm CF radius in a device operating at a temperature of 300 K). We propose a suppressed, effective TiO2 thermal conductivity to more accurately predict the CF temperature rise with the Heat Diffusion Equation.
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Nondiffusive Thermal Transport Increases Temperature Rise in RRAM Filaments
IEEE Electron Device Letters, 2016Co-Authors: Keith T. Regner, Jonathan A. MalenAbstract:Thermal transport in resistive random-access memory (RRAM) is modeled in the set state, where the conductive filament (CF) is approximated by an infinitely long cylinder embedded in crystalline rutile TiO2, a prototypical RRAM material. Determination of the phonon mean free path (MFP) spectrum in TiO2 shows that MFPs are similar to the CF radius, indicating that thermal transport is nondiffusive. We develop an analytical solution to the Boltzmann transport Equation (BTE) to model the nondiffusive thermal transport in TiO2 and find that the surface temperature rise of the CF predicted by the BTE is larger than that predicted by the Heat Diffusion Equation (e.g., $4\times $ larger for a 1 nm CF radius in a device operating at a temperature of 300 K). We propose a suppressed, effective TiO2 thermal conductivity to more accurately predict the CF temperature rise with the Heat Diffusion Equation.
Keith T. Regner - One of the best experts on this subject based on the ideXlab platform.
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Nondiffusive Thermal Transport Increases Temperature Rise in RRAM Filaments
IEEE Electron Device Letters, 2016Co-Authors: Keith T. Regner, Jonathan A. MalenAbstract:Thermal transport in resistive random-access memory (RRAM) is modeled in the set state, where the conductive filament (CF) is approximated by an infinitely long cylinder embedded in crystalline rutile TiO2, a prototypical RRAM material. Determination of the phonon mean free path (MFP) spectrum in TiO2 shows that MFPs are similar to the CF radius, indicating that thermal transport is nondiffusive. We develop an analytical solution to the Boltzmann transport Equation (BTE) to model the nondiffusive thermal transport in TiO2 and find that the surface temperature rise of the CF predicted by the BTE is larger than that predicted by the Heat Diffusion Equation (e.g., $4\times $ larger for a 1 nm CF radius in a device operating at a temperature of 300 K). We propose a suppressed, effective TiO2 thermal conductivity to more accurately predict the CF temperature rise with the Heat Diffusion Equation.
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Nondiffusive Thermal Transport Increases Temperature Rise in RRAM Filaments
IEEE Electron Device Letters, 2016Co-Authors: Keith T. Regner, Jonathan A. MalenAbstract:Thermal transport in resistive random-access memory (RRAM) is modeled in the set state, where the conductive filament (CF) is approximated by an infinitely long cylinder embedded in crystalline rutile TiO2, a prototypical RRAM material. Determination of the phonon mean free path (MFP) spectrum in TiO2 shows that MFPs are similar to the CF radius, indicating that thermal transport is nondiffusive. We develop an analytical solution to the Boltzmann transport Equation (BTE) to model the nondiffusive thermal transport in TiO2 and find that the surface temperature rise of the CF predicted by the BTE is larger than that predicted by the Heat Diffusion Equation (e.g., $4\times $ larger for a 1 nm CF radius in a device operating at a temperature of 300 K). We propose a suppressed, effective TiO2 thermal conductivity to more accurately predict the CF temperature rise with the Heat Diffusion Equation.
Christian Frétigny - One of the best experts on this subject based on the ideXlab platform.
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Analytical solutions of the Heat Diffusion Equation for 3ω method geometry
Journal of Applied Physics, 2010Co-Authors: Jean Yves Duquesne, D. Fournier, Christian FrétignyAbstract:“3ω” experiments aim at measuring thermal conductivities and diffusivities. Data analysis relies on integral expressions of the temperature. In this paper, we derive new explicit analytical formulations of the solution of the Heat Diffusion Equation, using Bessel, Struve, and Meijer-G functions, in the 3ω geometry for bulk solids. These functions are available in major computational tools. Therefore numerical integrations can be avoided in data analysis. Moreover, these expressions enable rigorous derivations of the asymptotic behaviors. We also underline that the diffusivity can be extracted from the phase data without any calibration while the conductivity measurement requires a careful one.
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Analytical solutions of the Heat Diffusion Equation for 3 omega method geometry
Journal of Applied Physics, 2010Co-Authors: Jean Yves Duquesne, D. Fournier, Christian FrétignyAbstract:“3ω” experiments aim at measuring thermal conductivities and diffusivities. Data analysis relies on integral expressions of the temperature. In this paper, we derive new explicit analytical formu- lations of the solution of the Heat Diffusion Equation, using Bessel, Struve and Meijer-G functions, in the 3ω geometry for bulk solids. These functions are available in major computational tools. Therefore numerical integrations can be avoided in data analysis. Moreover, these expressions enable rigorous derivations of the asymptotic behaviors. We also underline that the diffusivity can be extracted from the phase data without any calibration while the conductivity measurement requires a careful one.
S Aihara - One of the best experts on this subject based on the ideXlab platform.
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on adaptive boundary control for stochastic parabolic systems with unknown potential coefficient
IEEE Transactions on Automatic Control, 1997Co-Authors: S AiharaAbstract:An adaptive boundary control problem for a stochastic Heat Diffusion Equation is studied. The considered system contains an unknown potential coefficient which is a function of the spatial variables. The estimation algorithm for the unknown potential coefficient is proposed by using the stochastic approximation technique. After showing the strong consistency of the estimated parameter, the cost for the adaptive control scheme presented here is shown to converge to the optimal ergodic cost. Finally some numerical examples are shown.
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adaptive boundary control for stochastic parabolic systems with unknown potential coefficient
Conference on Decision and Control, 1994Co-Authors: S AiharaAbstract:An adaptive boundary control problem for a stochastic Heat Diffusion Equation is studied. The system considered contains the unknown potential coefficient which is a function of the spatial variables. The estimation algorithm for the unknown potential coefficient is proposed by using the stochastic approximation technique. After showing the strong consistency of the estimated parameter, the cost for the adaptive control scheme presented here is shown to converge to the optimal ergodic cost. Finally some numerical examples are shown. >
Larry J. Segerlind - One of the best experts on this subject based on the ideXlab platform.
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Dynamic time step and stability criteria comparison for the Heat Diffusion Equation
International Journal of Thermal Sciences, 1999Co-Authors: Rabi H. Mohtar, Larry J. SegerlindAbstract:Abstract Dynamic time step estimates were determined for four single step numerical schemes in one dimension, and three finite element and three finite difference single step schemes in two dimensions. Unlike other stability-based time step criteria, the dynamic time step estimates are functions of grid size, material properties, and boundary conditions. For a certain problem, an initial coarse mesh is required to determine its lowest eigenvalue. The problem needs to be re-meshed and solved with the new mesh to satisfy a desired accuracy. Correlations between the dynamic time step and the stability criteria were conducted. A stability criteria equivalence was defined as the stability criteria that gives a time step estimate equivalent to the dynamic time step estimate. For the range of problems solved and for the central difference time stepping scheme, the stability criteria equivalence ranges from 0.5 to 2.7 for one-dimensional problems and 0.46 to 9.13 for tqo-dimensional problems, depending on the problem boundary conditions. The study shows that, unlike the dynamic time step estimate, the stability criteria used for selecting a time step is not adequate, since it does not change with the problem boundary conditions.
