کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7907903 1510758 2018 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Tunable terahertz reflection spectrum based on band gaps of GaP materials excited by ultrasonic
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Tunable terahertz reflection spectrum based on band gaps of GaP materials excited by ultrasonic
چکیده انگلیسی
Tunable terahertz (THz) reflection spectrum, ranged from 0.2 to 8 THz, in band gaps of gallium phosphide (GaP) materials excited by ultrasonic is investigated in the present paper, in which tunable ultrasonic and terahertz wave collinear transmission in the same direction is postulated. Numerical simulation results show that, under the acousto-optic interaction, band gaps of transverse optical phonon polariton dispersion curves are turned on, this leads to a dis-propagation of polariton in GaP bulk. On the other side, GaP material has less absorption to THz wave according to experimental studies, as indicates that THz wave could be reflected by the band gaps spontaneously. The band gaps width and acousto-optic coupling strength are proportional with ultrasonic frequency and its intensity in ultrasonic frequency range of 0-250 MHz, in which low-frequency branch of transverse optical phonon polariton dispersion curves demonstrate periodicity and folding as well as. With the increase of ultrasonic frequency, frequency of band gap is blue-shifted, and total reflectivity decreased with −1-order and −2-order reflectivity decrease. The band gaps converge to the restrahlen band infinitely with frequency of ultrasonic exceeding over 250 MHz, total reflectivity of which is attenuated. As is show above, reflection of THz wave can be accommodated by regulating the frequency and its intensity of ultrasonic frequency. Relevant technology may be available in tunable THz frequency selection and filtering.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Optical Materials - Volume 76, February 2018, Pages 388-392
نویسندگان
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