GaAs光致发射极化电子源的原理及其在极化(e.2e)中的应用  

Principle of GaAs Photoemission Polarized Electron Source and Application in the Polarization (e,2e)

作　　者：李兴鳌[1] 桑斌[2] 肖渊[2] 阮存军[2] 庞文宁[2] 尚仁成[2] 

机构地区：[1]湖北民族学院物理系,湖北恩施445000 [2]清华大学物理系极化物理实验室,北京100084

出　　处：《湖北民族学院学报（自然科学版）》2002年第3期30-32,共3页Journal of Hubei Minzu University(Natural Science Edition)

基　　金：国家自然科学基金 ( 198740 3 7) ;省教育厅重点项目 ( 2 0 0 1A0 80 10 )

摘　　要：GaAs半导体光致发射极化电子源是 70年代末在国际上出现的一种新型极化电子源 .它采用GaAs半导体晶片作为光阴极 ,并在高真空环境下将碱金属铯及氧化剂镀到光阴极上 ,以获得负电子亲和势 (NegativeElectronAffinity)表面 ,然后通过用波长合适的圆偏振激光照射光阴极 ,来获得自旋极化的电子束 .详细讨论了GaAs半导体光致发射极化电子源的原理及实验过程 ,并介绍了极化电子在极化 (e ,2e)A GaAs photoemission polarized electron source is a new kind of polarized electron source which emerged in late 1970s. A GaAs semiconductor crystal is used as the photo-cathode, whose surface is plated by alkali metal Cesium and oxidizer under super high vacuum circumstance to obtain the Negative Affinity(NEA) surface. Under the irradiation of a beam of circular polarized laser with an appropriate wave length, spin polarized electrons can be emitted. The principle and experiment of GaAs photoemission polarized electron source has been discussed in detail in this thesis, and its application in polarization (e,2e) has been also introduced.

关 键 词：GaAs光致发射极化电子源 极化电子束 负电子亲和势 极化(e.2e) 砷化钙半导体 极化电子 碰撞电离 

分 类 号：O471.3[理学—半导体物理] TN304.22[理学—物理]