اثرات دما بر روی ضرایب شکست و ثابت کر بلورمایع نماتیک آلائیده شده با مواد راستگرد

خادم صدیق, مهسا

doi:10.22055/jrmbs.2024.18895

اثرات دما بر روی ضرایب شکست و ثابت کر بلورمایع نماتیک آلائیده شده با مواد راستگرد

نوع مقاله : مقاله پژوهشی کامل

نویسنده

مهسا خادم صدیق

گروه مهندسی اپتیک و لیزر، دانشگاه بناب، بناب ایران

10.22055/jrmbs.2024.18895

چکیده

بلورمایع‌ها با پاسخ‌های نوری و الکترواپتیکی بالا نقش مهمی در اپتیک و فوتونیک دارند. از این‌رو، ارائه روشی ساده برای افزایش رفتارهای نوری بلورمایع‌ها تحت تأثیر میدان‌های خارجی را می‌توان یکی از چالش ‌برانگیزترین حوزه‌های پژوهشی دانست. در این کار تجربی، اثرات دما و مادة کایرال راستگرد با درصدهای وزنی مختلف بر روی ضرایب شکست و خواص نوری بلورمایع نماتیک E7 تحت اعمال میدان خارجی مورد بررسی و مطالعه قرار گرفت. علیرغم کاهش ثابت کر با افزایش درصد وزنی آلاینده‌های کایرال و دما، بیشترین مقدار پاسخ نوری در حضور میدان الکتریکی برای بلور مایع نماتیک آلائیده شده با %3 از مادة راستگرد به‌دست آمد. در این حالت مقدار ثابت کر تقریباً 2 برابر نمونه بلورمایع خالص است. این نتیجه جالب می‌تواند مربوط به تغییرات پارامتر نظم ناشی از برهم‌کنش‌های مختلف مولکولی باشد. بدین ترتیب نتایج به‌دست آمده در این پژوهش می‌تواند به‌عنوان روشی ساده به‌منظور افزایش پاسخ نوری بلورمایع‌های نماتیک در حضور میدان الکتریکی خارجی مورد استفاده قرار گیرد.

کلیدواژه‌ها

موضوعات

اپتیک-لیزر

عنوان مقاله [English]

Temperature effect on the refractive indices and Kerr constant of doped nematic liquid crystals with right-handed dopants

نویسنده [English]

Mahsa Khadem Sadigh

Department of Laser and Optical Engineering, University of Bonab, Bonab, Iran

چکیده [English]

Liquid crystals with high optical and electro-optical responses play an important role in optics and photonics. Therefore, providing a simple method to increase the optical behavior of liquid crystals under the influence of external fields can be considered one of the most challenging research areas. In this experimental work, the effects of temperature and right-handed chiral material with different weight percentages on the refractive indices and optical properties of E7 nematic liquid crystal under the influence of an external electric field were investigated. Despite the reduction of the Kerr constant with increasing the weight percentage of chiral dopants and temperature, the highest amount of optical response in the presence of the electric field was obtained for the nematic liquid crystal doped with 3% of right-handed material. In this case, the value of the Kerr constant is almost 2 times that of pure liquid crystal. This interesting result can be related to the order parameter changes caused by different molecular interactions. Thus, the results obtained in this research can be used as a simple method to increase the optical response of nematic liquid crystals in the presence of an external electric field.

کلیدواژه‌ها [English]

Chiral
Electric field
Kerr Constant
Liquid Crystal
Refractive index
Temperature

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