Selected Applications
atto3DR
Angle Dependent Magnetoresistance Measurement
Due to the arbitrary orientation inherent to self-assembled materials on
the substrate, typical characterization techniques such as magnetoresis-
tance measurements conducted at cryogenic temperatures greatly benefit
from the possibility to freely change the mutual orientation of external
magnetic field and sample. Although this is easily possible e.g. by using
a 3D vector magnet setup, the associated costs (>> 100 k$) are often
prohibitive. Single axis sample rotator setups on the other hand not only
require choosing either an out-of-plane or in-plane configuration prior to
cooldown, but also put firm restrictions on certain measurements which
rely on a precise orientation of the field e.g. perpendicular or parallel to an
initially unknown direction along a sample structure. The perfect solution
to such applications is attocube’s 3-dimensional rotator atto3DR.
Similar to a recent publication by C. H. Butschkow and co-workers [1] from
the group of Prof. Dieter Weiss (Univ. of Regensburg), magnetotransport
measurements on individual GaAs/(Ga,Mn)As core-shell nanowires (top
figure) have been conducted.
The center figure shows magnetoresistance at 5 T as a function of the angle
between externally applied magnetic field and the nanowire axis for differ-
ent rotation planes: (orange) in-plane rotation, referring to the SiO 2 sub-
strate plane, (green) out of plane (perpendicular) rotation with the long
nanowire axis entirely in the rotation plane, and (blue) out of plane (trans-
versal) rotation with the rotation plane transversal to the nanowire axis.
The bottom figure shows the normalized magnetoresistance as a function
of the angle between externally applied magnetic field and the nanowire
axis for various magnitudes of the external magnetic field.
(measured by C. Butschkow in collaboration with attocube application labs 2012; sample courtesy of C.
Butschkow, University of Regensburg).
[1] C. Butschkow et al., Phys. Rev. B 87, 245303 (2013)
attoMICROSCOPY
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