Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatially controlled electrostatic doping in graphene p-i-n junction for
  hybrid silicon photodiode   Sufficiently large depletion region for photocarrier generation and
separation is a key factor for two-dimensional material optoelectronic devices,
but few device configurations has been explored for a deterministic control of
a space charge region area in graphene with convincing scalability. Here we
investigate a graphene-silicon p-i-n photodiode defined in a foundry processed
planar photonic crystal waveguide structure, achieving visible - near-infrared,
zero-bias and ultrafast photodetection. Graphene is electrically contacting to
the wide intrinsic region of silicon and extended to the p an n doped region,
functioning as the primary photocarrier conducting channel for electronic gain.
Graphene significantly improves the device speed through ultrafast out-of-plane
interfacial carrier transfer and the following in-plane built-in electric field
assisted carrier collection. More than 50 dB converted signal-to-noise ratio at
40 GHz has been demonstrated under zero bias voltage, with quantum efficiency
could be further amplified by hot carrier gain on graphene-i Si interface and
avalanche process on graphene-doped Si interface. With the device architecture
fully defined by nanomanufactured substrate, this study is the first
demonstration of post-fabrication-free two-dimensional material active silicon
photonic devices.

20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn