کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1675959 1518088 2006 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Room temperature synthesized GaAs quantum dot embedded in SiO2 composite film
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فناوری نانو (نانو تکنولوژی)
پیش نمایش صفحه اول مقاله
Room temperature synthesized GaAs quantum dot embedded in SiO2 composite film
چکیده انگلیسی

Nano-composite films, consisting of GaAs quantum dots embedded in SiO2 glass matrix, were fabricated and analyzed in terms of their structural, chemical, and optical properties. In order to fabricate uniformly dispersed GaAs quantum dots in the SiO2 matrix, composite films consisting of alternate layers of GaAs and SiO2 were deposited in the manner of a superlattice by radio frequency magnetron sputter deposition. In order to control the size of GaAs quantum dots the thickness of GaAs in individual layers was varied at a fixed GaAs total volume fraction. Transmission electron microscopy and X-ray photoelectron spectroscopy analyses revealed that GaAs quantum dots were in crystalline phase and in the form of a Ga–As compound. From optical absorbance measurements, absorption edges at visible wavelength band were determined and compared among composite films of varying GaAs nominal thickness. The amount of blue shift of the absorption edge increased with decreasing GaAs nominal thickness, i.e. quantum dots size. Band gaps of the composite films determined from Tauc plots and photoluminescence measurements exhibited a linear decrease with increasing GaAs nominal thickness. Large values of third-order non-linear optical susceptibility χ(3) (∼ 7.6 × 10− 14 m2/V2 at 488 nm), which were believed to originate due to the state filling effect, were observed.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Thin Solid Films - Volume 514, Issues 1–2, 30 August 2006, Pages 296–301
نویسندگان
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