یک روش بدون شبکۀ محلی به‌صورت قوی برای حل معادلۀ شرودینگر وابسته به زمان دوبعدی

نویسندگان
دانشگاه خلیج فارس، دانشکدۀ علوم پایه، گروه ریاضی، بوشهر
چکیده
در این مقاله یک روش بدون شبکۀ محلی بر پایۀ صورت قوی مسئله، برای حل معادلۀ دوبعدی وابسته به زمان شرودینگر داده شده است. ابتدا متغیر زمان با استفاده از یک روش تفاضلات متناهی مناسب گسسته‌سازی شده است. سپس، در معادلات بیضوی حاصل، متغیر مکانی با استفاده از روش توابع پایه‌ای شعاعی محلی که در آن عملگر معادلۀ دیفرانسیل جزئی نیز در ماتریس‌های محلی اعمال شده، گسسته‌سازی شده است. در روش ارائه شده، برخلاف روش‌های هم‌محلی سراسری، با تقسیم دامنۀ هم‌محلی سراسری به تعداد زیادی زیر ناحیه‌های محلی، پایداری روش به شدّت افزایش می‌یابد. به‌علاوه، به‌دلیل استفاده از صورت قوی و روش هم‌محلی، که نیاز به محاسبۀ انتگرال ندارد، و هم‌چنین به‌دلیل این‌که در عملیات ماتریسی، ماتریس‌ها با بعد کوچک هستند، هزینۀ محاسبات کاهش می‌یابد. برای خطی‌سازی معادلات غیرخطی، روشی تکراری معرفی شده است. دو مثال خطی و دو مثال غیرخطی با جواب تحلیلی معلوم و یک مثال غیرخطی با جواب نامعین و شرایط مرزی متناوب به‌وسیلۀ این روش آزموده شده‌اند و نتایج عددی نشان‌دهندۀ دقّت بالا و کارایی روش است
کلیدواژه‌ها

عنوان مقاله English

A Local Strong form Meshless Method for Solving 2D time-Dependent Schrödinger Equations

نویسندگان English

Fariba Takhtabnoos
Ahmad Shirzadi
Persian Gulf University, Iran
چکیده English

This paper deals with the numerical solutions of the 2D time dependent Schr¨odinger equations by using a local strong form meshless method. The time variable is discretized by a finite difference scheme. Then, in the resultant elliptic type PDEs, special variable is discretized with a local radial basis function (RBF) methods for which the PDE operator is also imposed in the local matrices. Despite the global collocation approaches, dividing the global collocation domain into many local subdomains, the stability of the method increases. Furthermore, because of the use of strong form equation and collocation approach, which does not need integration, and since in the matrix operations the matrices are of small size, computational cost decreases. An iterative approach is proposed to deal with the nonlinear term. Two linear and two nonlinear test problems with known exact solutions are considered and then, the simulation to a nonlinear problem with unknown solution and periodic boundary conditions is also presented and the results reveal that the method is efficient../files/site1/files/42/3Abstract.pdf

کلیدواژه‌ها English

Local radial basis functions meshless methods
Collocation methods
Finite differences
Schrödinger equation
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