نویسندگان

دانشگاه صنعتی مالک اشتر اصفهان

چکیده

در کار حاضر برخی خواص فیزیکی دو تک‌بلور KTP < /span> و RTP < /span> مورد بررسی قرارگرفته است. اثر جانشانی روبیدیم بر خواص ساختاری، الکترونی و اپتیکی KTP < /span> بررسی شده است. محاسبات با استفاده از امواج تخت بهبودیافته خطی با پتانسیل کامل در چارچوب نظریه تابعی چگالی انجام‌گرفته است. خواص ساختاری با استفاده از تابعی‌های تبادلی- همبستگی متفاوت LDA، PBE، WC و PBEsol محاسبه شده است. همچنین برای محاسبه مقدار انرژی گاف تقریب PBEsol و جهت محاسبه دقیق‌تر، تقریب mBJ به کار گرفته شده است. پدیده شبه وارونی دو بلور بررسی و مقادیر آن برای هر دو بلور با استفاده از نرم‌افزار محاسبه شده است. اثر جانشانی روبیدیم بر شبه تقارن KTP < /span> و همچنین ارتباط این کمیت با خواص اپتیکی غیرخطی مورد بحث قرار گرفته است. ضرایب اپتیکی از جمله ضریب شکست، مقادیر دوشکستی و ضرایب جذب با استفاده از تابع دی‌الکتریک محاسبه گردیده، درباره وجود ناهمسانگردی در هر دو بلور بحث و نتایج مقایسه شده‌اند.

کلیدواژه‌ها

عنوان مقاله [English]

Ab- initio investigation of physical properties of KTP and RTP

نویسندگان [English]

  • Marzieh Ghoohestani
  • Ali Arab
  • Hossein Sadeghi

چکیده [English]

In this work,the physical properties of  KTP and RTP single-crystals have been investigated by performing accurate total energy calculations in the framework of density functional theory by using the full-potential linearized augmented plane wave method. The effects of Rb substitution on structural, electronic and optical properties of KTP are discussed. The structural properties have been calculated by using different exchange correlation including LDA, PBE, WC and PBEsol. Also PBEsol approximation and and more accurate approximation mBJ are employed to calculate the energy gap values. The Pseudoinversion values of both crystals have been calculated by using PseudoSymmetry software . Rb substitution effect on pseudosymmetry of KTP and also relation between second-order susceptibility of crystals and the Pseudoinversion values are discussed. The optical coefficients such as refractive index, birefringence values and absorption coefficients have been calculated by using the dielectric function. The anisotropy in the linear optical properties of KTP and RTP crystals have been demonstrated. Then calculated results have been compared.

کلیدواژه‌ها [English]

  • density functional theory -structural
  • electronic and optical properties- Pseudoinversion-dielectric function-anisotropy-birefringence

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