Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum transport theory for nanostructures with Rashba spin-orbital
  interaction   We report on a general theory for analyzing quantum transport through devices
in the Metal-QD-Metal configuration where QD is a quantum dot or the device
scattering region which contains Rashba spin-orbital and electron-electron
interactions. The metal leads may or may not be ferromagnetic, they are assumed
to weakly couple to the QD region. Our theory is formulated by second
quantizing the Rashba spin-orbital interaction in spectral space (instead of
real space), and quantum transport is then analyzed within the Keldysh
nonequilibrium Green's function formalism. The Rashba interaction causes two
main effects to the Hamiltonian: (i) it gives rise to an extra spin-dependent
phase factor in the coupling matrix elements between the leads and the QD; (ii)
it gives rise to an inter-level spin-flip term but forbids any intra-level
spin-flips. Our formalism provides a starting point for analyzing many quantum
transport issues where spin-orbital effects are important. As an example, we
investigate transport properties of a Aharnov-Bohm ring in which a QD having
Rashba spin-orbital and e-e interactions is located in one arm of the ring. A
substantial spin-polarized conductance or current emerges in this device due to
a combined effect of a magnetic flux and the Rashba interaction. The direction
and strength of the spin-polarization are shown to be controllable by both the
magnetic flux and a gate voltage.

24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess