GaAs/AlGaAs Hall Sensor and a BSCCO disk on top of the Sensor
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Sample size effect on vortex matter in Bi2212Vortex matter in
BSCCO has many phases-vortex liquid, 3D and 2D solid due to the extreme
anisotropy and high Tc (90K) of this layered material. However,
when the sample size approaches the vortex correlation length, vortex
matter phase transitions could be effected and even vanish below a
critical sample size at a given temperature. With micron-sized Bi2212 and
a GaAs/AlGaAs Hall sensor (left) for local magnetization measurements, we
observed that at a given temperature, the vortex solid 3D-2D transition
disappears below a critical sample size Rcr. Rcr
agrees well with the vortex correlation length of the Larkin-Ovchinnikov
collective pinning model. For details, see our publication in Phys. Rev.
Lett.
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