摘要
离子辐照可以改变二氧化硅(SiO_(2))的晶体结构和光学性质.采用645 MeV Xe^(35+)离子辐照SiO_(2)单晶,在辐照过程中,利用光栅光谱仪测量在200—800 nm范围内的光发射.在发射光谱中,观测到中心位于461和631 nm的发射带.这些发射带是弗伦克尔激子辐射退激产生的,其强度与辐照离子能量和辐照离子剂量密切相关.实验结果表明:发射光强随离子在固体中的电子能损呈指数增加.由于离子辐照对晶体造成损伤,发射光谱强度随辐照剂量的增加而降低.文中讨论了这些与晶体结构有关的发射带,结合能量损失机制讨论了激子形成和退激过程.快重离子辐照过程中发射光谱的原位测量对研究辐照改性具有重要意义,有助于揭示离子辐照引起晶体损伤的物理机制.
Silicon dioxide(SiO_(2)) is an important component of nuclear reactor optical fiber and is also a candidate material for wast solidification.Owing to its special physical and chemical characteristics,it is used in many different technology fields like optics,electronics,energy orspace.Swift heavy ion irradiation can modify the crystal structure and optical property of optical material SiO_(2).Swift heavy ions deposit their energy mainly by inelastic interaction.Highly ionized lattice atoms may be formed along the trajectory,and a fraction of their electrical energy can be converted directly into the kinetic energy of the ions.The irradiation experiment is performed with Xeq+ions at the irradiation terminal of the sector-focused cyclotron at heavy-ion research facility in Lanzhou(HIRFL).The on-line spectral measurement experiment is carried out during irradiation.In the darkroom,the UV-visible light emission from the target is focused into optical fiber by a collimating lens,and then is analyzed with the Sp-2558 spectrometer equipped with a 1200 g/mm optical grating blazed at500 nm.In the present work,SiO_(2)single crystals are irradiated with 93-609 MeV Xeq+ions with a dose in a range of 1×1011-3×1011ions/cm~2.During irradiation,the emission spectra,in a range of 200-800 nm,from SiO_(2)irradiated by 93,245,425 and 609 MeV Xeq+ions,are obtained.Two emission bands centered at 461 and631 nm are observed.These emission bands are produced by Frenkel exciton radiation de-excitation and their intensities are closely related to the irradiated ion energy and radiation dose.The results show that the light intensity increases with the electron energy loss index increasing.And owing to crystal damage caused by ion irradiation,the intensity of emission spectrum decreases with the augment of irradiation dose.Ion loses its energy throughout the ion track via Sn and Se interacting with target atoms and electrons respectively,and the energy lost by the ion is estimated by using SRIM code.The SRIM simulated ion ranges and recoil
作者
徐秋梅
缑洁
张崇宏
杨治虎
王彦瑜
韩旭孝
李建洋
Xu Qiu-Mei;Gou Jie;Zhang Chong-Hong;Yang Zhi-Hu;Wang Yan-Yu;Han Xu-Xiao;Li Jian-Yang(Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2023年第4期53-64,共12页
Acta Physica Sinica
基金
国家自然科学基金(批准号:12104463,U1532262)资助的课题。
关键词
带状发射谱
快重离子
电子能损
二氧化硅
optical emission band
swift heavy ions
the electron energy loss
silicon dioxide
