Particle size-dependent superspin glass behavior in random compacts of monodisperse maghemite nanoparticles

• Dense random assemblies made from highly monodisperse gamma-Fe2O3 nanoparticles with sizes ranging from 6.2 to 11.5 nm have been investigated by DC and AC magnetometry. It is found that all assemblies undergo superspin glass phase transitions. The superspin glass phase transition temperature is strongly dependent on the particle size and the nature of the interparticle interaction. However the transition from superparamagnet to superspin glass, as evidenced by the shape of the ac-susceptibility curves and the dynamic critical exponents associated with the transition, is similar in all systems.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Materialteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering (hsv//eng)

Nyckelord

magnetic nanoparticles

maghemite

superspin glass

phase transition

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)