Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: All-optical switching due to state-filling in quantum dots   We report all-optical switching due to state-filling in quantum dots (QDs)
within a Mach-Zehnder Interferometric (MZI) switch. The MZI was fabricated
using InGaAsP/InP waveguides containing a single layer of InAs/InP QDs. A
1530-1570 nm probe beam is switched by optical excitation of one MZI-arm from
the top. By exciting below the InGaAsP bandgap, we prove that the refractive
index nonlinearity is only due to the QDs. The switching efficiency is 2
rad/(microW absorbed power). Probe wavelength insensitivity was obtained using
a broad distribution of QDs.

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The categories of this paper are: physics
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
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The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat