Time-resolved spectroscopic behavior of Fe2O3 and ZnFe2O4 nanocrystals

doi:10.1063/1.1640340

CORC > 化学研究所 > 中国科学院化学研究所

	Time-resolved spectroscopic behavior of Fe2O3 and ZnFe2O4 nanocrystals
	Fu, LM ; Wu, ZY ; Ai, XC ; Zhang, JP ; Nie, YX ; Xie, SS ; Yang, GZ ; Zou, BS
刊名	JOURNAL OF CHEMICAL PHYSICS
	2004-02-15
卷号	120 期号:7 页码:3406-3413
ISSN号	0021-9606
DOI	10.1063/1.1640340
英文摘要	Using nanosecond (ns) and femtosecond (fs) time-resolved absorption spectroscopies (pump-probe technique), the carrier dynamics in transition metal oxide nanocrystals of alpha-Fe2O3 and ZnFe2O4 was studied during the photolysis process. For Fe2O3 and ZnFe2O4 nanocrystals, the fs measurements detect similar profiles of a positive nonlinear absorption in their capped nanocrystals, whereas much weak signals in the naked particles. In the nanosecond measurements Fe2O3 and ZnFe2O4 nanocrystals show obvious excitation-power dependent absorption properties and at the low pump power they show weak photobleaching, but at high pump power they produce positive nonlinear absorptions. For Fe2O3 nanocrystals, the threshold power of negative absorption (bleach) to positive absorption increases with reducing size, whereas for the ZnFe2O4 samples, the threshold powers reach minimum at a critical size of 11 nm, grow for both the bigger and the smaller nanocrystals. These results reflect the influences of their microscopic magnetic couplings and carrier correlation on biexciton absorption in Fe2O3 and ZnFe2O4 nanocrystals. All the results indicate that the time resolved photoabsorption techniques are useful to study the microscopic spin interactions and carrier correlations in transition metal oxide nanocrystals. (C) 2004 American Institute of Physics.
语种	英语
出版者	AMER INST PHYSICS
WOS记录号	WOS:000188880900043
内容类型	期刊论文
源URL	[http://ir.iccas.ac.cn/handle/121111/55397]
专题	中国科学院化学研究所
通讯作者	Fu, LM
作者单位	1.Chinese Acad Sci, Inst Phys, Nanophys & Nanodevice Lab, Beijing 100080, Peoples R China 2.Chinese Acad Sci, Inst Chem, State Key Lab Struct Chem Unstable & Stable Speci, Beijing 100080, Peoples R China
推荐引用方式 GB/T 7714	Fu, LM,Wu, ZY,Ai, XC,et al. Time-resolved spectroscopic behavior of Fe2O3 and ZnFe2O4 nanocrystals[J]. JOURNAL OF CHEMICAL PHYSICS,2004,120(7):3406-3413.
APA	Fu, LM.,Wu, ZY.,Ai, XC.,Zhang, JP.,Nie, YX.,...&Zou, BS.(2004).Time-resolved spectroscopic behavior of Fe2O3 and ZnFe2O4 nanocrystals.JOURNAL OF CHEMICAL PHYSICS,120(7),3406-3413.
MLA	Fu, LM,et al."Time-resolved spectroscopic behavior of Fe2O3 and ZnFe2O4 nanocrystals".JOURNAL OF CHEMICAL PHYSICS 120.7(2004):3406-3413.