Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Broadband Transistor-Injected Dual Doping Quantum Cascade Laser   A novel design-friendly device called the transistor-injected dual doping
quantum cascade laser (TI-D2QCL) with two different doping in each stack of a
homogeneous superlattice is proposed. By adjusting the base-emitter bias Vbe of
the bipolar transistor to supply electrons in the dual doping regions, charge
quasi-neutrality can be achieved to generate different optical transitions in
each cascading superlattice stack. These transitions are then stacked and
amplified to contribute to a broad flat gain spectrum. Model calculations of a
designed TI- D2QCL show that a broad flat gain spectrum ranging from 9.41um to
12.01um with a relative bandwidth of 0.24 can be obtained, indicating that the
TI- D2QCL with dual doping pattern may open a new pathway to the appealing
applications in both MIR and THz frequency ranges, from wideband optical
generations to advanced frequency comb technologies.

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The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
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The categories of this paper are: econ
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org