Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Carrier and Spin Coherent Dynamics in Strained Germanium-Tin
  Semiconductor on Silicon   Germanium-Tin is emerging as a material exhibiting excellent photonic
properties. Here we demonstrate optical initialization and readout of spins in
this intriguing group IV semiconductor alloy and report on spin quantum beats
between Zeeman-split levels under an external magnetic field. Our optical
experiments reveal robust spin orientation in a wide temperature range and a
persistent spin lifetime that approaches the ns regime at room temperature.
Besides important insights into nonradiative recombination pathways, our
findings disclose a rich spin physics in novel epitaxial structures directly
grown on a conventional Si substrate. This introduces a viable route towards
the synergic enrichment of the group IV semiconductor toolbox with advanced
spintronics and photonic capabilities.

15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci