کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1866886 1038086 2014 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Boundary-limited thermal conduction of crystalline rods oriented near phonon-focusing caustics
ترجمه فارسی عنوان
هدایت حرارتی محدودی از میله های بلوری که در نزدیکی اتم های فوکوس کننده فوکوس قرار دارند
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک و نجوم (عمومی)
چکیده انگلیسی


• Casimir thermal conduction in anisotropic rods oriented near phonon-focusing caustics is studied theoretically.
• In the direction of an external conical refraction caustic the Casimir limit does not exist.
• For fold and cusp caustics the Casimir conductivity remains finite.
• Analytical expressions describing the Casimir conductivity in the vicinity of caustics are obtained.

We apply the Casimir model for boundary-limited heat conduction to single-crystal rods oriented near phonon-focusing caustics. We show that rods with axes close to the direction of an external conical refraction caustic, a highly degenerate caustic that exists for certain hexagonal crystals, exhibit a thermal conductivity that diverges logarithmically on approaching the caustic. For rods with axes close to the directions of the more generic fold and cusp caustics, the conductivity remains finite, but displays singular behavior with a 1/2- or 1/3-power law falloff with angular deviation from the caustic. Moreover, in the direction of a fold caustic, the Casimir conduction is not necessarily a maximum. Numerical results are presented for zinc, with the quasi-transverse branch providing examples of the external conical refraction and fold caustics, and in a certain sense, also the cusp caustic.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physics Letters A - Volume 378, Issue 45, 3 October 2014, Pages 3372–3381
نویسندگان
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