Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A single-frequency single-resonator laser on erbium-doped lithium
  niobate on insulator   Erbium-doped lithium niobate on insulator (Er:LNOI) is a promising platform
for photonic integrated circuits as it adds gain to the LNOI system and enables
on-chip lasers and amplifiers. A challenge for Er:LNOI laser is to increase its
output power while maintaining single-frequency and single (-transverse)-mode
operation. In this work, we demonstrate that single-frequency and single-mode
operation can be achieved even in a single multi-mode Er:LNOI microring by
introducing mode-dependent loss and gain competition. In a single microring
with a free spectral range of 192 GHz, we have achieved single-mode lasing with
an output power of 2.1 microwatt, a side-mode suppression of 35.5 dB, and a
linewidth of 1.27 MHz.

13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex