CAJ | 학술논문

由于纳米碳管的优异机械特性及其丰富多采的光学和电学特性,它自1991年被发现以来一下受到科学家的青睐.纳米碳管研究已成为当今世界上发展最迅速,竞争最激烈的科学前沿领域之一.怎样才能把纳米碳管做得更细小,尺寸更均匀以及如何使众多的纳米碳管排列规整,一下是纳米碳管研究中的难题.我们利用多孔的沸石晶体作为载体,首次成功地研制出了尺寸均一,排列规整的超细单壁纳米碳管.这些超细纳米碳管具有独特的性能,低温下(<20K)甚至呈现出前所未有的一维超导现象.详细介绍了这些超细单壁纳米碳管制制备过程,并着重介绍其在可见光区的光吸收,光发射以及二次谐波的倍频特性.
유우납미탄관적우이궤계특성급기봉부다채적광학화전학특성,타자1991년피발현이래일하수도과학가적청래.납미탄관연구이성위당금세계상발전최신속,경쟁최격렬적과학전연영역지일.즘양재능파납미탄관주득경세소,척촌경균균이급여하사음다적납미탄관배렬규정,일하시납미탄관연구중적난제.아문이용다공적비석정체작위재체,수차성공지연제출료척촌균일,배렬규정적초세단벽납미탄관.저사초세납미탄관구유독특적성능,저온하(<20K)심지정현출전소미유적일유초도현상.상세개소료저사초세단벽납미탄관제제비과정,병착중개소기재가견광구적광흡수,광발사이급이차해파적배빈특성.
We report the polarized optical absorption and photoluminescence spectra of single-walled 0.4nm carbon nanotubes (SWNTs) arrayed in the channels of an A1PO4-5(AFI)single crystal.When the light electric field(E) is polarized parallel to the tube direction(c),the absorption spectrum display a sharp peak at 1.37eV with two broad bands at 2.eV and 3.1eV.The intensities of these absorption bands gradually decrease as the polarization angle is varied from 0?(E\\c)to 90?(E/c configuration ,the tube is nearly transparent in the measured energy region of 0.5-4.1eV.The photoluminescence observed around 700nm also shows strong polarization dependence.Under high power excitation using the rundamental frequency of a YAG laser ,the sample shows strong strong nonlinear up-conversion emission around 700nm and high efficeint second-harmonic generation.The mechanism of the nonliner photoluminescence and SHG is not clear yet.