Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ultrasensitive N-photon interferometric autocorrelator   We demonstrate a novel method to measure the Nth-order (N=1, 2, 3, 4)
interferometric autocorrelation with high sensitivity and temporal resolution.
It is based on the combination of linear absorption and nonlinear detection in
a superconducting nanodetector, providing much higher efficiency than methods
based on all-optical nonlinearities. Its temporal resolution is only limited by
the quasi-particle energy relaxation time, which is directly measured to be in
the 20 ps range for the NbN films used in this work. We present a general model
of interferometric autocorrelation with these nonlinear detectors and discuss
the comparison with other approaches and possible improvements.

24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
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The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas