12250

11221

كارشناسي ارشد

ماده چگال

اصفهان: دانشگاه صنعتي اصفهان، دانشكده فيزيك

1395

نه، 74ص.: مصور، جدول، نمودار

ص. ع. به فارسي و انگليسي

مجتبي اعلائي

هادي اكبرزاده

ممتحن داخلي: اسماعيل عبدالحسيني سارسري; ممتحن خارجي: جواد هاشمي فر

1395/12/08

كتابنامه

فيزيك

فيزيك

ID11221

Investigation of Optical properties of Silicon Nanoclusters Sin Hm Si8 Si80 Shima Heydarian s heydarian@ph iut ac ir December 20 2016 Department of Physics Isfahan University of Technology Isfahan 84156 83111 Iran University Code IUT 77142 Degree M S c Language Farsisupervisor Dr M Alaeim alaei@cc iut ac irAbstractSilicon nanoclusters has been attracted in recent decades because of their appli cations in di erent industries such as optoelectronic microelectronic solarcellsand medical industry Because optical gap of Silicon Nanoparticles quantum dots are tunable by theirsize they are intersting we can mentione photoluminescence e ect in roomtemprature as an other properties of Si nanostructures As we know optical prop erties including absorption energy optical gap and emission energy and becausein this project we consider application of these type of clusters in solar cells hencewe will investigate their absorbtion spectrum and calculate their optical gap Absorption spectrum of Silicon nanoclusters are depend on their geometry sizeof clusters and passivation of dangling bonds In most works bulk like structureshave been considered dangling were passivated bonds by di erent elements likehydrogen Oxygen Fluorin and etc Con nement e ect has been investigated forbulk like structures and according to it optical gap of bulk like structures de creases by increasing the size of clusters In this project we want to consider structures which obtained by a sophisticatedmethod evolutionary algorithm by USPEX package For these structures we in vestigate absorption spectrum and optical gap As we know density functional theory is a ground state theory and for calculationof absorption spectrum system should be considered under external perturbation like electromagnetism eld hence we have to use time dependent theory Hencewe use di erent methods for calculation of optical gap At rst step optical gap of structures are calculated by TD DFTB method andthen optical gap are calculated by turbo TDDFT and TD DFT to increasethe accuracy of computaions Keywords optoelectronic industry microelectronic photoluminescencee ect quantum con nement e ect dangling bond optical gap TD DFTB theory turbo TDDFT method

مجتبي اعلائي

هادي اكبرزاده

ممتحن داخلي: اسماعيل عبدالحسيني سارسري; ممتحن خارجي: جواد هاشمي فر