نویسندگان

گروه فیزیک، دانشگاه قم، قم

چکیده

در این مقاله خواص اپتیکی نانوساختارهای هرمی شکل نقره با استفاده از تقریب دوقطبی مجزا در محیط آب مورد بررسی قرار گرفت. سطح مقطع‌های جذب، پراکندگی و خاموشی این دسته از نانوساختارها بر حسب تغییرات طول موج نور فرودی در ناحیه مرئی و فروسرخ نزدیک محاسبه شد. همچنین تغییرات ارتفاع، طول موج و پهنای نواری قله‌های سطح مقطع خاموشی (ناشی از تشدید پلاسمونی) بر حسب اندازه نانوذرات و ثابت دی الکتریک محیط مورد بررسی قرار گرفت. نتایج نشان می‌دهد که تنها دو قله مد دو قطبی و چهار قطبی در این طیف وجود دارد.

کلیدواژه‌ها

عنوان مقاله [English]

Study of Optical Properties of Ag Pyramid Nanostructures by Discrete Dipole Approximation Method

نویسندگان [English]

  • S Ranjbar
  • A Azarian

چکیده [English]

In this paper, we investigate optical properties of silver pyramid nanostructures (SPNs) by means of discrete dipole approximation (DDA), when these nanoparticles are embedded into the water. Absorption, scattering and extinction cross-sections of the SPNs were calculated by change of incident wavelength in visible and near infra-red region. Moreover, height, wavelength and full width at half maximum (FWHM) of extinction cross-section peaks (due to plasmon resonances) were studied by change of nanostructure's size and dielectric constant of medium. Our results show that, there are only two peaks of dipole and quadruple modes in this spectrum.

کلیدواژه‌ها [English]

  • Ag pyramid nanostructures
  • Discrete Dipole Approximation
  • plasmon
  • Cross-sections

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