Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin and valley-orbit splittings in SiGe/Si heterostructures   Spin and valley-orbit splittings are calculated in SiGe/Si/SiGe quantum wells
(QWs) by using the tight-binding approach. In accordance with the symmetry
considerations an existence of spin splitting of electronic states in perfect
QWs with an odd number of Si atomic planes is microscopically demonstrated. The
spin splitting oscillates with QW width and these oscillations related to the
inter-valley reflection of an electron wave from the interfaces. It is shown
that the splittings under study can efficiently be described by an extended
envelope-function approach taking into account the spin- and valley-dependent
interface mixing. The obtained results provide a theoretical base to the
experimentally observed electron spin relaxation times in SiGe/Si/SiGe QWs.

5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th