Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Controlled Stark shifts in Er$^{3+}$-doped crystalline and amorphous
  waveguides for quantum state storage   We present measurements of the linear Stark effect on the $^{4}$I$_{15/2}
\to$ $^{4}$I$_{13/2}$ transition in an Er$^{3+}$-doped proton-exchanged
LiNbO$_{3}$ crystalline waveguide and an Er$^{3+}$-doped silicate fiber. The
measurements were made using spectral hole burning techniques at temperatures
below 4 K. We measured an effective Stark coefficient
$(\Delta\mu_{e}\chi)/(h)=25\pm1$kHz/Vcm$^{-1}$ in the crystalline waveguide and
$(\bar{\Delta\mu_{e}}\chi)/(h)=15\pm1$kHz/Vcm$^{-1}$ in the silicate fiber.
These results confirm the potential of Erbium doped waveguides for quantum
state storage based on controlled reversible inhomogeneous broadening.

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The categories of this paper are: supr-con
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
15
The categories of this paper are: nucl-ex