%0 Journal Article
%T Optical Properties of GaNAs and GaAsSb Semiconductors<br>GaNAs和GaAsSb半导体的光学性质研究（英文）
%A LUO Xiang-Dong
%A XU Zhong-Ying
%A <br>罗向东
%A 徐仲英
%J 中国科学院研究生院学报
%D 2005
%I 
%X Under short pulse laser excitation,it has been observed,for the first time,a new high-energy photoluminescence emission from GaN_ x As_ 1- x /GaAs SQWs.This new emission has totally different optical properties compared with the localized exciton transition in GaN_ x As_ 1- x ,and is attributed to the recombination of delocalized excitons in QWs.At the same time,a competition process between localized and delocalized exciton emissions in GaN_ x As_ 1- x /GaAs quantum wells is observed in the temperature-dependent PL spectra under the short pulse excitation. This competition process for the first time,reveals the physical origin of the temperature-induced S-shaped PL peak shift,which was often reported in the disordered alloy semiconductor system under continuous-wave excitation and puzzled people for a long time.We have also investigated a set of GaN_ x As_ 1- x samples with small nitrogen composition( x <1%)by PL,and time-resolved PL.After the PL dependence on temperature and excitation power and PL dynamics were measured,the new PL peak was identified as an intrinsic transition of alloy,rather than N-related bound states.This is the first observation in PL,showing that alloy state exists in GaN_ x As_ 1- x materials even when N composition is smaller than 0.1%. Finally by selective excitation,both type-I and type-II transitions were observed simultaneously in GaAs_ 1- x Sb_ x /GaAs SQWs for the first time.
%K GaNAs
%K GaAsSb
%K optical property
%K localized and delocalized
%K selective excitation<br>GaNAs
%K GaAsSb
%K 光学性质
%K 局域和非局域
%K 选择激发
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=B5EDD921F3D863E289B22F36E70174A7007B5F5E43D63598017D41BB67247657&cid=B47B31F6349F979B&jid=67CDFDECD959936E166E0F72DE972847&aid=D3020D590192DC6A&yid=2DD7160C83D0ACED&vid=CA4FD0336C81A37A&iid=94C357A881DFC066&sid=9107B2E171152411&eid=04FC77FB58A9B53A&journal_id=1002-1175&journal_name=中国科学院研究生院学报&referenced_num=0&reference_num=49