MAGNETIC AND OPTICAL-PROPERTIES OF GAMMA-FE2O3 NANOCRYSTALS

被引:184
作者
VASSILIOU, JK
MEHROTRA, V
RUSSELL, MW
GIANNELIS, EP
MCMICHAEL, RD
SHULL, RD
ZIOLO, RF
机构
[1] CORNELL UNIV,CTR MAT SCI,ITHACA,NY 14853
[2] CORNELL UNIV,DEPT MAT SCI & ENGN,ITHACA,NY 14853
[3] NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899
[4] XEROX CORP,WEBSTER RES CTR,WEBSTER,NY 14580
关键词
D O I
10.1063/1.353784
中图分类号
O59 [应用物理学];
学科分类号
摘要
Gamma-Fe2O3 nanocrystals have been synthesized in a polymer matrix by an ion exchange and precipitation reaction. The particles are crystalline with a mean diameter of 85 angstrom. The unit cell volume is 1735.2 angstrom3 corresponding to a unit cell compression of 0.35%. Magnetization and susceptibility data from experiment and computer simulations indicate that the system is superparamagnetic. The calculated magnetic anisotropy for the particles is two orders of magnitude larger than that of bulk gamma-Fe2O3. The optical absorption edge is red shifted with respect to that of an epitaxially grown single-crystal film of gamma-Fe2O3. The red shift is attributed to lattice strain in the small particles.
引用
收藏
页码:5109 / 5116
页数:8
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