A5057388191- Advanced Mathematical Physics Problems
- Nonlinear Photonic Systems
- Nonlinear Waves and Solitons
- Spectral Theory in Mathematical Physics
- Quantum Computing Algorithms and Architecture
- Radio Frequency Integrated Circuit Design
- Quantum Information and Cryptography
- Quantum and electron transport phenomena
- Stability and Controllability of Differential Equations
- Numerical methods for differential equations
- Advanced Power Amplifier Design
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum many-body systems
- Electromagnetic Compatibility and Noise Suppression
- Nonlinear Partial Differential Equations
- Quantum-Dot Cellular Automata
- Numerical methods in inverse problems
- 3D IC and TSV technologies
- Quantum chaos and dynamical systems
- Advanced DC-DC Converters
- High Temperature Alloys and Creep
- Navier-Stokes equation solutions
- Silicon Carbide Semiconductor Technologies
- GaN-based semiconductor devices and materials
- Microstructure and mechanical properties
Chiba University
2013-2024
University of Trieste
2020
Tohoku University
1972-2013
Kyoto University
2008-2011
Panasonic (Japan)
1988-2003
We apply our idea, which previously we used in the analysis of pure power NLS, consisting spitting virial inequality method into a large energy combined with Kato smoothing, to case generalized Korteweg--De Vries equations. assume that solution remains for all positive times very close soliton and then prove an asymptotic stability result $t\to +\infty$.
A novel technology that drastically improves output power and efficiency of amplifiers has been developed, where source load second-harmonic impedances, as well the fundamental are optimally terminated in input matching circuits. record high 74% power-added (PAE) with 31.4 dBm (1.4 W) at a frequency 930 MHz achieved single-stage saturated amplifier using an ion-implanted GaAs MESFET under low supply voltage 3.5 V. As linear amplifier, excellent PAE 59% 31.5 realized V/sub d/=4.7 V f=948 MHz....
We describe the asymptotic behavior of small energy solutions an NLS with a trapping potential. In particular we generalize work Soffer and Weinstein, Tsai et. al. The novelty is that allow generic spectra associated to This yet new application idea interpret nonlinear Fermi Golden Rule as consequence Hamiltonian structure.
.We extend the result of Kowalczyk, Martel, and Muñoz [J. Eur. Math. Soc. (JEMS), 24 (2022), pp. 2133–2167] on existence, in context spatially even solutions, asymptotic stability a center hypersurface at soliton defocusing power nonlinear Klein–Gordon equation with \(p\gt 3\) , to case \(2\ge p\gt \frac{5}{3}\) . The is attained performing new refined estimates that allow us close argument for law range .Keywordsconditional stabilitynonlinear Klein–Gordonsolitonvirial estimatesFermi golden...
Abstract We investigate the minimizers of energy functional under constraint L 2 -norm. show that for case -norm is small, minimizer unique and large, concentrate at maximum point b decays exponentially. By this result, we can if V are radially symmetric but does not attain its maxi- mum origin, then symmetry breaking occurs as increases. Further, has several points, concentrates a which minimizes function defined by b, positive radial solution -∆φ + φ - p = 0. For when symmetric, symmetric....
We study large time behavior of quantum walks (QWs) with self-dependent (nonlinear) coin. In particular, we show scattering and derive the reproducing formula for inverse in weak nonlinear regime. The proof is based on space-time estimate (linear) QWs such as dispersive estimates Strichartz estimate. Such argument standard Schrödinger equations discrete but it seems to be first applied QWs.
We consider a nonlinear Schrödinger equation (NLS) with very general term and trapping $\delta $ potential on the line. then discuss asymptotic behavior of all its small solutions, generalizing recent result by Masaki, Murphy, Segata [Anal. PDE, to appear] means virial-like inequalities. give also dispersion in case defocusing equations nontrapping delta potential.
Abstract We present some numerical results for nonlinear quantum walks (NLQWs) studied by the authors analytically (Maeda et al 2018 Discrete Contin. Dyn. Syst. 38 3687–3703; Maeda Quantum Inf. Process. 17 215). It was shown that if nonlinearity is weak, then long time behavior of NLQWs are approximated linear walks. In this paper, we observe decay range wider than in 3687–3703). addition, treat strong regime and show solitonic solutions appears. There several kinds soliton dynamics becomes...
<p style='text-indent:20px;'>We give short survey on the question of asymptotic stability ground states nonlinear Schrödinger equations, focusing primarily so called Fermi Golden Rule.
We provide a detailed proof that the Nonlinear Fermi Golden Rule coefficient appears in our recent of asymptotic stability ground states for pure power Schr\"odinger equations $\mathbb{R}$ with exponent $0<|p-3|\ll 1$ is nonzero.
Assuming the nonlinear Fermi Golden Rule (FGR) and no resonance at threshold of continuous spectrum linearization assuming furthermore as hypotheses results proved numerically by Chang et al. \cite{Chang} for exponent $p\in (3,5)$, we prove that ground states Schr\"odinger equation (NLS) with pure power nonlinearity $p$ in line are asymptotically stable a certain set values where FGR occurs means discrete mode 3rd or 4th order interaction mode. The argument is similar to our recent result...
Low-power GaAs ICs and power modules have been developed for 150-cc-type cellular telephones. The front-end IC splitter can operate under 3 V, the dissipation current is only half that of Si bipolar ICs. IC, consisting a low-noise amplifier, local downconverter, shows conversion gain 22 dB at -15 dBm. used in dividing output voltage-controlled oscillator supplying to two mixers, an 0 dBm internal isolation over 25 dB. module as transmitter, composed two-stage hybrid amplifier using MESFETs,...
We prove the existence of a two-parameter family small quasi-periodic solutions discrete nonlinear Schrödinger equation (DNLS). further show that all DNLS decouple to one these and dispersive wave. As byproduct, we bound states including excited are stable.