Operating regime and stability of mode-locking in 10GHz quantum dot laser diodes around 1.5µm

In this paper we investigate and explore the stability and operating regime of modelocking (ML) in 4mm long Fabry-Perot type lasers, corresponding to a roundtrip frequency of 10GHz. The devices are fabricated on InAs/InP quantum dot material, operating at wavelengths around 1.5um, and are HR-coated at the absorber side. In order to find the stable ML region of operation in these devices, we have performed sweep-scans on the injection current of the gain section, and the reverse bias voltage on the absorber section. We will present the optical and electrical spectrum of devices with different absorber length. These results will be compared with the performance of earlier devices without HR coating

Monolithic multiband nanosecond programmable wavelength router

A compact scalable reconfigurable multiwavelength router is proposed and demonstrated using an electronically gated cyclic router. Simultaneous wavelength-multiplexed channel allocation is performed with power penalties of 0.2-0.8 dB. Nanosecond timescale reconfiguration is achieved within a 2-ns guard band using semiconductor optical amplifier gates

Multi-wavelength laser based on an arrayed waveguide grating and Sagnac loop reflectors monolithically integrated on InP

In this paper, a multi-wavelength laser monolithically integrated on InP is presented. A linear laser cavity is built between two integrated Sagnac loop reflectors, with an Arrayed Waveguide Grating (AWG) as frequency selective device, and Semiconductor Optical Amplifiers (SOA) as gain sections. The power is out coupled from the cavity using a side diffraction order of the AWG. Simultaneous laser operation is provided for four wavelengths/cavities in the device. The termination of the laser cavities with integrated Sagnac loop reflectors avoids using high reflection coating. Only anti-reflection coating is used in the output facet of the chip

InP monolithically integrated label swapper device for spectral amplitude coded optical packet networks

In this paper a label swapping device, for spectral amplitude coded optical packet networks, fully integrated using InP technology is presented. Compared to previous demonstrations using discrete component assembly, the device footprint is reduced by a factor of 105 and the operation speed is increased by a factor of 103. This is, to the best of our knowledge, the first demonstration of a totally integrated label swapping device

Passively Mode-Locked 4.6 and 10.5 GHz Quantum Dot Laser Diodes Around 1.55 mu m With Large Operating Regime

tum dot laser diodes operating at wavelengths around 1.55 µm is reported. For a 4.6-GHz laser, a large operating regime of stable mode-locking, with RF-peak heights of over 40 dB, is found for injection currents of 750 mA up to 1.0 A and for values of the ab-sorber bias voltage of 0 V down to −3 V. Optical output spectra are broad, with a bandwidth of 6–7 nm. However, power exchange between different spectral components of the laser output leads to a relatively large phase jitter, resulting in a total timing jitter of around 35 ps. In a 4-mm-long, 10.5-GHz laser, it is shown that the operating regime of stable mode-locking is limited by the appear-ance of quantum dot excited state lasing, since higher injection current densities are necessary for these shorter lasers. The out-put pulses are stretched in time and heavily up-chirped with a value of 16–20 ps/nm. This mode of operation can be compared to Fourier domain mode-locking. The lasers have been realized using a fabrication technology that is compatible with further photonic integration. This makes such lasers promising candidates for, e.g., a coherent multiwavelength source in a complex photonic chip. Index Terms—Mode-locked lasers, quantum dots, semiconduc-tor lasers. I

Measurement of the cross section for isolated-photon plus jet production in pp collisions at √s=13 TeV using the ATLAS detector

The dynamics of isolated-photon production in association with a jet in proton–proton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fb−1. Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti- algorithm with radius parameter and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photon–jet invariant mass and the scattering angle in the photon–jet centre-of-mass system. Tree-level plus parton-shower predictions from Sherpa and Pythia as well as next-to-leading-order QCD predictions from Jetphox and Sherpa are compared to the measurements