کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1546082 997607 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Acoustic phonons transport in a quantum waveguide embedded double defects
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد مواد الکترونیکی، نوری و مغناطیسی
پیش نمایش صفحه اول مقاله
Acoustic phonons transport in a quantum waveguide embedded double defects
چکیده انگلیسی
By using scattering matrix method, we investigate the acoustic phonons transport in a quantum waveguide embedded double defects at low temperatures. When acoustic phonons propagate through the waveguide, the total transmission coefficient versus the reduced phonon frequency exhibits a series of resonant peaks and dips, and acoustic waves interfere with each other in the waveguide to form standing wave with particular wavelengths. In the waveguide with void defects, acoustic phonons whose frequencies approach zero can transport without scattering. The acoustic phonons propagating in the waveguide with clamped material defects, the phonons frequencies must be larger than a threshold frequency. It is also found that the thermal conductance versus temperature is qualitatively different for different types of defects. At low temperatures, when the double defects are void, the universal quantum thermal conductance and a thermal conductance plateau can be clearly observed. However, when the double defects consist of clamped material, the quantized thermal conductance disappears but a threshold temperature where mode 0 can be excited emerges. The results can provide some references in controlling thermal conductance artificially and the design of phonon devices.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physica E: Low-dimensional Systems and Nanostructures - Volume 41, Issue 10, October 2009, Pages 1864-1871
نویسندگان
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