• Special Issue
  • Nonlinear Integrated Photonics: Current Status and Future Trends
  • 12 Article (s)
Tuning the second-harmonic generation in AlGaAs nanodimers via non-radiative state optimization [Invited]
Davide Rocco, Valerio F. Gili, Lavinia Ghirardini, Luca Carletti, Ivan Favero, Andrea Locatelli, Giuseppe Marino, Dragomir N. Neshev, Michele Celebrano, Marco Finazzi, Giuseppe Leo, and Costantino De Angelis
Photonics Research
  • Publication Date: Apr. 11, 2018
  • Vol. 6, Issue 5, 050000B6 (2018)
Dual-polarization wavelength conversion of 16-QAM signals in a single silicon waveguide with lateral p-i-n diode [Invited]
Francesco Da Ros, Andrzej Gajda, Erik Liebig, Edson P. da Silva, Anna Pęczek, Peter D. Girouard, Andreas Mai, Klaus Petermann, Lars Zimmermann, Michael Galili, and Leif K. Oxenløwe
Photonics Research
  • Publication Date: Apr. 11, 2018
  • Vol. 6, Issue 5, 05000B23 (2018)
Photonic microwave true time delays for phased array antennas using a 49  GHz FSR integrated optical micro-comb source [Invited]
Xingyuan Xu, Jiayang Wu, Thach G. Nguyen, Tania Moein, Sai T. Chu, Brent E. Little, Roberto Morandotti, Arnan Mitchell, and David J. Moss
We demonstrate significantly improved performance of a microwave true time delay line based on an integrated optical frequency comb source. The broadband micro-comb (over 100 nm wide) features a record low free spectral range (FSR) of 49 GHz, resulting in an unprecedented record high channel number (81 over the C band)—the highest number of channels for an integrated comb source used for microwave signal processing. We theoretically analyze the performance of a phased array antenna and show that this large channel count results in a high angular resolution and wide beam-steering tunable range. This demonstrates the feasibility of our approach as a competitive solution toward implementing integrated photonic true time delays in radar and communications systems.
Photonics Research
  • Publication Date: Apr. 12, 2018
  • Vol. 6, Issue 5, 05000B30 (2018)
Nonlinear optical properties of integrated GeSbS chalcogenide waveguides
Samuel Serna, Hongtao Lin, Carlos Alonso-Ramos, Anupama Yadav, Xavier Le Roux, Kathleen Richardson, Eric Cassan, Nicolas Dubreuil, Juejun Hu, and Laurent Vivien
In this paper, we report the experimental characterization of highly nonlinear GeSbS chalcogenide glass waveguides. We used a single-beam characterization protocol that accounts for the magnitude and sign of the real and imaginary parts of the third-order nonlinear susceptibility of integrated Ge23Sb7S70 (GeSbS) chalcogenide glass waveguides in the near-infrared wavelength range at λ=1580 nm. We measured a waveguide nonlinear parameter of 7.0±0.7 W 1·m 1, which corresponds to a nonlinear refractive index of n2=(0.93±0.08)×10 18 m2/W, comparable to that of silicon, but with an 80 times lower two-photon absorption coefficient βTPA=(0.010±0.003) cm/GW, accompanied with linear propagation losses as low as 0.5 dB/cm. The outstanding linear and nonlinear properties of GeSbS, with a measured nonlinear figure of merit FOMTPA=6.0±1.4 at λ=1580 nm, ultimately make it one of the most promising integrated platforms for the realization of nonlinear functionalities.
Photonics Research
  • Publication Date: Apr. 13, 2018
  • Vol. 6, Issue 5, 05000B37 (2018)
Nonlinear optics on silicon-rich nitride—a high nonlinear figure of merit CMOS platform [Invited]
D. T. H. Tan, K. J. A. Ooi, and D. K. T. Ng
CMOS platforms with a high nonlinear figure of merit are highly sought after for high photonic quantum efficiencies, enabling functionalities not possible from purely linear effects and ease of integration with CMOS electronics. Silicon-based platforms have been prolific amongst the suite of advanced nonlinear optical signal processes demonstrated to date. These include crystalline silicon, amorphous silicon, Hydex glass, and stoichiometric silicon nitride. Residing between stoichiometric silicon nitride and amorphous silicon in composition, silicon-rich nitride films of various formulations have emerged recently as promising nonlinear platforms for high nonlinear figure of merit nonlinear optics. Silicon-rich nitride films are compositionally engineered to create bandgaps that are sufficiently large to eliminate two-photon absorption at telecommunications wavelengths while enabling much larger nonlinear waveguide parameters (5x–500x) than those in stoichiometric silicon nitride. This paper reviews recent developments in the field of nonlinear optics using silicon-rich nitride platforms, as well as the outlook and future opportunities in this burgeoning field.
Photonics Research
  • Publication Date: Apr. 16, 2018
  • Vol. 6, Issue 5, 05000B50 (2018)
Type-II micro-comb generation in a filter-driven four wave mixing laser [Invited]
Hualong Bao, Andrew Cooper, Sai T. Chu, Dave J. Moss, Roberto Morandotti, Brent E. Little, Marco Peccianti, and Alessia Pasquazi
We experimentally demonstrate the generation of highly coherent Type-II micro-combs based on a micro-resonator nested in a fiber cavity loop, known as the filter-driven four wave mixing (FD-FWM) laser scheme. In this system, the frequency spacing of the comb can be adjusted to integer multiples of the free-spectral range (FSR) of the nested micro-resonator by properly tuning the fiber cavity length. Sub-comb lines with single FSR spacing around the primary comb lines can be generated. Such a spectral emission is known as a “Type-II comb”. Our system achieves a fully coherent output. This behavior is verified by numerical simulations. This study represents an important step forward in controlling and manipulating the dynamics of an FD-FWM laser.
Photonics Research
  • Publication Date: Apr. 16, 2018
  • Vol. 6, Issue 5, 05000B67 (2018)

Advances in integrated optoelectronics and nanophotonics have been very rich in recent years. These include the spectacular developments of nonlinear group four photonic platforms as well as the integration of components and functions based on III-V semiconductor materials. One of the strongest trends for the future is the development of all-optical signal processing functions within integrated, compact, low-loss devices, paving the way for new applications. This approach, relying on materials, components and the integration of optical functions, is based on a wide range of exciting physical phenomena, exploiting the nonlinear optical response of materials for the generation of frequency combs, the conversion of light wavelength, the generation of supercontinuum radiation, and many other phenomena exploiting the unprecedented power of light control by waves. This special issue has drawn a critical overview of the recent and significant burgeoning advances in the field, as well as to identify the next technological and scientific milestones to come for the development of integrated nonlinear photonics. Meanwhile, it aims to shed light on the interdisciplinary dimension of the work carried out in the field, based, for example, on the control of optical waves by acoustic waves, opening the way to the fields of nonlinear optomechanics and optoacoustics.