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Title: Ultrafast second-order nonlinear photonics—from classical physics to non-Gaussian quantum dynamics: a tutorial

Photonic integrated circuits with second-order (χ(2)) nonlinearities are rapidly scaling to remarkably low powers. At this time, state-of-the-art devices achieve saturated nonlinear interactions with thousands of photons when driven by continuous-wave lasers, and further reductions in these energy requirements enabled by the use of ultrafast pulses may soon push nonlinear optics into the realm of single-photon nonlinearities. This tutorial reviews these recent developments in ultrafast nonlinear photonics, discusses design strategies for realizing few-photon nonlinear interactions, and presents a unified treatment of ultrafast quantum nonlinear optics using a framework that smoothly interpolates from classical behaviors to the few-photon scale. These emerging platforms for quantum optics fundamentally differ from typical realizations in cavity quantum electrodynamics due to the large number of coupled optical modes. Classically, multimode behaviors have been well studied in nonlinear optics, with famous examples including soliton formation and supercontinuum generation. In contrast, multimode quantum systems exhibit a far greater variety of behaviors, and yet closed-form solutions are even sparser than their classical counterparts. In developing a framework for ultrafast quantum optics, we identify what behaviors carry over from classical to quantum devices, what intuition must be abandoned, and what new opportunities exist at the intersection of ultrafast and quantum nonlinear optics. Although this article focuses on establishing connections between the classical and quantum behaviors of devices withχ(2)nonlinearities, the frameworks developed here are general and are readily extended to the description of dynamical processes based on third-orderχ(3)nonlinearities.

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Award ID(s):
2011363 1918549 2137723
PAR ID:
10543215
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Optica
Date Published:
Journal Name:
Advances in Optics and Photonics
Volume:
16
Issue:
2
ISSN:
1943-8206
Page Range / eLocation ID:
347
Subject(s) / Keyword(s):
quantum optics nonlinear optics photonics
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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