Detection of picosecond magnetization dynamics of 50 nm magnetic dots down to the single dot regime

Bivas Rana; Dheeraj Kumar; Saswati Barman; Semanti Pal; Yasuhiro Fukuma; YoshiChika Otani; Anjan Barman

doi:10.1021/nn202791g

Detection of picosecond magnetization dynamics of 50 nm magnetic dots down to the single dot regime

ACS Nano. 2011 Dec 27;5(12):9559-65. doi: 10.1021/nn202791g. Epub 2011 Nov 4.

Authors

Bivas Rana¹, Dheeraj Kumar, Saswati Barman, Semanti Pal, Yasuhiro Fukuma, YoshiChika Otani, Anjan Barman

Affiliation

¹ Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098, India.

PMID: 22035409
DOI: 10.1021/nn202791g

Abstract

We report an all-optical time-domain detection of picosecond magnetization dynamics of arrays of 50 nm Ni(80)Fe(20) (permalloy) dots down to the single nanodot regime. In the single nanodot regime the dynamics reveals one dominant resonant mode corresponding to the edge mode of the 50 nm dot with slightly higher damping than that of the unpatterned thin film. With the increase in areal density of the array both the precession frequency and damping increase significantly due to the increase in magnetostatic interactions between the nanodots, and a mode splitting and sudden jump in apparent damping are observed at an edge-to-edge separation of 50 nm.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Equipment Design
Equipment Failure Analysis
Magnetics / instrumentation*
Materials Testing / methods*
Nanostructures / chemistry*
Nanostructures / ultrastructure*
Particle Size