Kaur Sukhnandan, Singh Surinder, Singh Lakhwant
Department of Physics, Guru Nanak Dev University, Amritsar 143005, Punjab, India.
Department of Physics, Guru Nanak Dev University, Amritsar 143005, Punjab, India.
Appl Radiat Isot. 2017 Mar;121:116-121. doi: 10.1016/j.apradiso.2016.12.053. Epub 2016 Dec 29.
Thin cleaved samples (~18µm) of natural muscovite mica were irradiated with 80MeV oxygen ion beam at fluence ranging from 1×10 to 5×10ion/cm. The alterations in dielectric, structural, chemical and thermoluminescence properties of irradiated as well as pristine samples have been investigated. Dielectric constant decreases while other dielectric parameters such as dielectric loss, tanδ, ac conductivity real and imaginary parts of electric modulus increase with increase of ion fluence. Williamson Hall investigation has been utilized to ascertain crystallite size and micro strain of pristine and irradiated samples. The XRD analysis revealed a significant increase in micro strain and dislocation density with an increase of ion fluence. The variations in dielectric properties upon irradiation are collaborated with structural modifications in the muscovite. No appreciable changes in characteristic bands (FTIR) have been observed after irradiation, indicating that natural muscovite mica is chemically stable. Natural muscovite mica has eminent applications in heavy ions dosimetry due to observation of well defined single peak at 303°C with activation energy of 1.24eV in TL spectrum.
将天然白云母薄片（~18µm）用能量为80MeV的氧离子束辐照，辐照通量范围为1×10至5×10离子/cm²。对辐照后的样品以及原始样品的介电、结构、化学和热释光特性的变化进行了研究。随着离子通量的增加，介电常数降低，而其他介电参数如介电损耗、tanδ、交流电导率、电模量的实部和虚部则增加。利用威廉姆森-霍尔分析法确定原始样品和辐照后样品的微晶尺寸和微观应变。X射线衍射分析表明，随着离子通量的增加，微观应变和位错密度显著增加。辐照后介电性能的变化与白云母中的结构改性有关。辐照后未观察到特征带（傅里叶变换红外光谱）有明显变化，表明天然白云母在化学上是稳定的。由于在热释光光谱中观察到在303°C有明确的单峰，活化能为1.24eV，天然白云母在重离子剂量测定中有显著应用。
