Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Impact of the valley orbit coupling on exchange gate for spin qubits in
  silicon quantum dots   The presence of degenerate conduction band valleys and how they are mixed by
interfaces play critical roles in determining electron interaction and spectrum
in a silicon nanostructure. Here we investigate how the valley phases affect
the exchange interaction in a symmetric two-electron silicon double quantum
dot. Through a configuration interaction calculation, we find that exchange
splitting is suppressed at a finite value of valley phase difference between
the two dots, and reaches its minimum value ({\sim} 0) when the phase
difference is {\pi}. Such a suppression can be explained using the Hubbard
model, through the valley-phase-dependent dressing by the doubly occupied
states on the ground singlet and triplet states. The contributions of the
higher orbital states also play a vital role in determining the value of the
exchange energy in general, which is a crucial parameter for applications such
as exchange gates for spin qubits.

16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
1
The categories of this paper are: cs