Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Excitonic Aharonov-Bohm Effect in Isotopically Pure 70Ge/Si Type-II
  Quantum Dots   We report on a magneto-photoluminescence study of isotopically pure 70Ge/Si
self-assembled type-II quantum dots. Oscillatory behaviors attributed to the
Aharonov-Bohm effect are simultaneously observed for the emission energy and
intensity of excitons subject to an increasing magnetic field. When the
magnetic flux penetrates through the ring-like trajectory of an electron moving
around each quantum dot, the ground state of an exciton experiences a change in
its angular momentum. Our results provide the experimental evidence for the
phase coherence of a localized electron wave function in group-IV Ge/Si
self-assembled quantum structures.

24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ