Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Surface dominated transport in single crystalline nanoflake devices of
  topological insulator Bi1.5Sb0.5Te1.8Se1.2   We report experimental evidence of surface dominated transport in single
crystalline nanoflake devices of topological insulator Bi1.5Sb0.5Te1.8Se1.2.
The resistivity measurements show dramatic difference between the nanoflake
devices and bulk single crystal. The resistivity and Hall analysis based on a
two-channel model indicates that ~99% surface transport contribution can be
realized in 200 nm thick BSTS nanoflake devices. Using standard bottom gate
with SiO2 as a dielectric layer, pronounced ambipolar electric field effect was
observed in devices fabricated with flakes of 100 - 200 nm thick. Moreover,
angle-dependent magneto-resistances of a nanoflake device with thickness of 596
nm are fitted to a universal curve for the perpendicular component of the
applied magnetic field. The value of phase coherence length obtained from 2D
weak antilocalization fitting further confirmed the surface dominated
transport. Our results open a path for realization of novel electric and
spintronic devices based on the topological helical surface states.

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The categories of this paper are: eess
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg