Investigation of artificial domains realized by local gallium focused ion-beam modification of Pt/Co/Pt trilayer structures

Journal Article · Sat Apr 15 04:00:00 EDT 2006 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2159393· OSTI ID:20788112

Aziz, A; Bending, S J; Roberts, H; Crampin, S; Heard, P J; Marrows, C H ^[1]

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1. Department of Physics, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom)

We present the results of experimental investigations of magnetic switching and magnetotransport in a generation of magnetic devices containing artificially patterned domains. Our devices are realized by locally reducing the coercive field of a perpendicularly magnetized Pt(3.5 nm)/Co(0.5 nm)/Pt(1.6 nm) trilayer structure using a gallium focused ion beam. Artificial domain walls are created at the interfaces between dosed and undosed regions when an external magnetic field switches the former but not the latter. We have exploited this property to create stripelike domains with widths down to submicron length scales, separated by undosed regions. Using the extraordinary Hall effect to monitor the local magnetization we have investigated the reversal dynamics of these artificial domains by measuring major and minor hysteresis loops. The coercive field of regions irradiated with identical doses systematically increases as their size decreases. In the lower branch of minor loops, reversal is seen to occur via a few large Barkhausen events. Preliminary measurements of transport across domain walls reveal a positive domain-wall resistance, that does not change sign from 4.2 to 300 K.

• OSTI ID: 20788112
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 99; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COBALT
COERCIVE FORCE
FERROMAGNETIC MATERIALS
GALLIUM
HALL EFFECT
HYSTERESIS
INTERFACES
ION BEAMS
MAGNETIC FIELDS
MAGNETIZATION
PLATINUM
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0000-0013 K
TEMPERATURE RANGE 0013-0065 K
TEMPERATURE RANGE 0065-0273 K
TEMPERATURE RANGE 0273-0400 K