Sains Malaysiana 40(1)(2011): 13–15

 

Thermal-Induced Non-Linearity of Ag Nano-fluid Prepared Using γ-Radiation Method

(Induksi-Terma Ketidak-Linearan Nanocecair Ag disedia Menggunakan Kaedah Sinaran-γ)

 

Esmaeil Shahriari, W. Mahmood Mat Yunus*, Zainal Abidin Talib & Elias Saion

Department of Physics, Universiti Putra Malaysia

43400 UPM, Serdang, Selangor D.E., Malaysia

 

Diserahkan: 7 Disember 2009 / Diterima: 13 Julai 2010

 

ABSTRACT

 

The non-linear refractive index of Ag nano-fluids prepared by γ-radiation method was investigated using a single beam z-scan technique. Under CW 532 nm laser excitation with power output of 40 mW, the Ag nano-fluids showed a large thermal-induced non-linear refractive index. In the present work it was determined that the non-linear refractive index for Ag nano-fluids is -4.80×10-8 cm2/W. The value of Δn0 was calculated to be -2.05×10-4. Our measurements also confirmed that the non-linear phenomenon was caused by the self-defocusing process making them good candidates for non linear optical devices.

 

Keywords: γ-radiation; nanofluid; non-linear refractive index; z-scan

 

ABSTRAK

 

Indek biasan taklinear nanocecair Ag yang disediakan dengan kaedah sinaran-γ telah dikaji menggunakan teknik imbasan-z alur laser tunggal. Di bawah pengujaan laser CW 532 nm dengan kuasa sinaran 40 mW, nanocecair Ag telah menunjukkan satu sifat indeks biasan tak-linear yang besar. Dalam kajian ini ditentukan bahawa indek biasan tak-linear untuk Ag adalah -4.80×10-8 cm2/W. Nilai Δn0 telah dikira dan bernilai 2.05×10-4. Pengukuran kami juga mengesahkan bahawa fenomena tak-linear adalah disebabkan oleh proses nyahfokus-dirian membuatkan ianya calon yang baik untuk reka bentuk optik tak-linear.

Kata kunci: Imbasan-z; indek biasan tak-linear; nanocecair; sinaran-γ

 

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*Pengarang untuk surat-menyurat; email: mahmood@science.upm.edu.my

 

 

 

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