- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2019 21st International Conference on Transparent Optical Networks (ICTON) - Angers, France (2019.7.9-2019.7.13)] 2019 21st International Conference on Transparent Optical Networks (ICTON) - Non-Hermitian Broad Aperture Semiconductor Lasers Based on PT-Symmetry
摘要： In this paper we propose a novel configuration to regularize the complex spatiotemporal dynamics of broad area lasers into bright light beam. It has recently been shown that arbitrary non-Hermitian optical potentials based on local Parity-Time (PT-) symmetry may tailor and control the flow of light, due to the asymmetric mode coupling. We now provide a comprehensive analysis on how this can be applied to stabilize the emission from broad aperture semiconductor lasers. The mechanism relies on a non-Hermitian configuration of the laser potential achieved by simultaneous spatial modulation of the refractive index and gain-loss profiles. This allows concentrating the light into a bright and narrow output beam. We provide a numerical analysis on Vertical Cavity Surface Emitting lasers and Broad Area Semiconductor Lasers. The results indicate a significant intensity enhancement and concentration of the emitted stabilized beam. The proposed mechanism may be technologically achievable, and it is expected to be applicable to regularize the radiation of other broad aperture and microlasers, which typically emit quite random and irregular light patterns. Besides, the reported concentration effect is universal, and could be extended to random and quasi-periodic background potentials.
关键词： semiconductor lasers,VCSEL,local PT-symmetry,non-Hermiticity
更新于2025-09-11 14:15:04
-
[IEEE 2019 Compound Semiconductor Week (CSW) - Nara, Japan (2019.5.19-2019.5.23)] 2019 Compound Semiconductor Week (CSW) - InP-based devices integrating liquid crystals microcells for a tunable laser emission or a wavelength selective photodetection
摘要： Photonic devices with wavelength tuning capabilities are investigated with the use of liquid crystal microcells monolithically integrated onto the surfaces of photodiodes or VCSEL fabricated on InP based materials. For these two devices, we demonstrated that the detected or emitted wavelength can be selected on a tuning range of more than 70 nm in the case of the photodiode, and of more than 20 nm in the case of VCSEL.
关键词： VCSEL,Photodiodes,Liquid-crystal,Optical communications
更新于2025-09-11 14:15:04
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - VCSEL Technologies for High-Capacity Dense WDM Networks
摘要： Long-wavelength vertical cavity surface emitting laser (VCSEL) technologies can represent an alternative solution for the development of transmitters with reduced cost, power consumption and footprint for very-high capacity metropolitan area systems. Exploiting direct modulation (DM) and advanced modulation formats, such as discrete multitone (DMT), and aggregating multiple DM-VCSELs emitting in the C-band with dense wavelength division multiplexers (WDM) in SOI chips allows to achieve multi-Tb/s transmitter module with 25 GHz granularity [1]. The interplay between the frequency chirp induced by VCSELs DM and the tight filtering of network WDM multiplexers plays a crucial role in the transmission performance. In this paper, we compare the adoption of two different long-wavelength InP VCSEL technologies: high-bandwidth short-cavity devices and MEMS-based widely-tuneable VCSELs [1]. We evaluate their performance in case of DM employing DMT modulation, providing more than 50-Gb/s capacity per wavelength; coherent detection (COH-D) is used to target hundreds of kilometres distances thanks to DSP chromatic dispersion (CD) compensation.
关键词： WDM,DMT,direct modulation,coherent detection,VCSEL
更新于2025-09-11 14:15:04
-
Interaction between Optical Sources and Optical Modulators for High-Speed Optical Communication Networks
摘要： The study shows the basic interaction between different optical sources and optical detectors for high-speed optical communication networks. Optical sources that are namely continuous wave (CW) laser, laser rate equations as well as the vertical cavity surface emitting laser (VCSEL). The utilized optical modulators are indicated as Mach Zehnder modulator (MZM) as well as the Electro-absorption modulator (EAM). The data rate available 40 Gb/s for propagation length ranges from 10 km to 50 km. It is observed that the interaction between CW laser/MZM or CW laser/EAM has presented better performance than other combinations. In order to measure the system performances, many interesting parameters have been investigated. These can be including the electrical received power, highest signal quality factor, Optical signal per noise ratio as well as the lowest data error rates.
关键词： VCSEL and high-speed networks,EAM,MZM,CW laser
更新于2025-09-11 14:15:04
-
Wearable SiPM-based NIRS Interface Integrated with Pulsed Laser Source
摘要： We present the design of a miniaturized probe integrating silicon photomultiplier and light-pulsing electronics in a single 2x2mm2 CMOS chip which includes functional blocks such as a fast pulse-laser driver and synchronized single-photon detection circuit. The photon pulses can be either counted on-chip or processed by an external high-speed electronic module such as time-corelated single photon counting (TCSPC) unit. The integrated circuit was assembled on a printed circuit board (PCB) and also on a 2.5D silicon interposer platform of size 1 cm and interfaced with a silicon photomultiplier (SiPM), vertical cavity surface emitting laser (VCSEL) and other ancillary components such as capacitors and resistors. Our approach of integrating an optical interface to optimize light collection on the small active area and light emission from the vertical-cavity surface-emitting laser (VSCEL) will facilitate clinical adoption in many applications and change the landscape of Near Infrared Spectroscopy (NIRS) hardware commercially due to significant optode-size reduction and the elimination of optical fibers.
关键词： Near-Infrared Spectroscopy (NIRS),Time-Domain (TD),complementary metal-oxide-semiconductor (CMOS),Vertical Cavity Surface Emitting Laser (VCSEL),Silicon Photomultiplier (SiPM),Optical Probe
更新于2025-09-11 14:15:04
-
Polarisation responses of a solitary and optically injected vertical cavity spin laser
摘要： The polarisation properties of a quantum well spin – vertical cavity surface emitting laser (spin – VCSEL), both without injection and with variable polarisation optical injection, are investigated experimentally and compared with the spin flip model (SFM). Without injection, we demonstrate two distinct types of VCSEL-pump response depending on the signs of the linewidth enhancement factor, birefringence and dichroism: firstly where the pump and VCSEL have the same sign of the ellipticity, and secondly where the VCSEL ellipticity, accompanied by the linear polarisation, switches sign. We show that by controlling the injected power, ellipticity or linear angle, near circular polarisation can be obtained. These responses both give insight into the electro-optical injected spin-VCSEL system, and have practical implications for the use of spin VCSELs in unique applications exploiting the ellipticity degree of freedom.
关键词： VCSEL,polarization,spin,injection
更新于2025-09-11 14:15:04
-
Optimized arrangement of vertical cavity surface emitting laser arrays to improve thermal characteristics
摘要： An optimization method for an arrangement of vertical cavity surface emitting laser (VCSEL) arrays to improve thermal characteristics of the arrays is presented. The method is based on the principle of minimum potential energy and is implemented by a self-organizing algorithm. The thermal and electrical properties of the active regions of the unoptimized and optimized arrays were obtained by a self-consistent thermoelectric simulation of the VCSEL structure based on the finite element method. The output characteristics of the unoptimized and optimized 4 × 4 square VCSEL arrays were studied theoretically and practically. The results showed that the optimized arrays have improved thermal characteristics.
关键词： VCSEL arrays,optimization method,thermal characteristics,self-organizing algorithm,finite element method
更新于2025-09-11 14:15:04
-
Cavity solitons in driven vertical-cavity-surface-emitting lasers above threshold as all-optical frequency mixers
摘要： Through numerical experiments, we show the ability of cavity solitons (CSs) forming in injection locked vertical-cavity-surface-emitting lasers to act as frequency mixers owing to their nonlinear essence. A conventional electronic frequency mixer employs two oscillators, local and signal, and generates different combined frequencies from those of the input. It is specifically shown here that considering various configurations for the device by arranging the local and signal oscillators, CSs can be cast as all-optical or optoelectronic frequency mixers. The feasibility of the proposed schemes has been checked via the frequency mismatch between the two oscillators and their relative strength.
关键词： cavity soliton,vertical-cavity-surface-emitting laser (VCSEL),modulation
更新于2025-09-11 14:15:04
-
Anisotropic lateral oxidation of Al-III-V semiconductors: inverse problem and circular aperture fabrication
摘要： The lateral wet oxidation of aluminum-containing III-V-semiconductors is a technological process which converts a buried (thin) cristalline material into an amorphous insulator and, as such, tends to exhibit an anisotropic behavior. As a result, the shape of the interface between the semiconductor and the insulator, often referred as the oxide aperture, differs from the etched mesa contour from which the oxidation proceeds. This, in turn, complicates the design of the devices relying on this process especially when specific oxide patterns are needed. In this paper, we introduce a method based on a morphological dilatation to determine the shape of the mesas which will lead to a specific targetted contour upon an anisotropic oxidation over a modest extent. The approach is experimentally validated by demonstrating the fabrication of circular oxide apertures which are inherently difficult to make because of their high degree of symmetry but which also turn out to be of critical importance in obtaining efficient single-mode vertical-cavity surface-emittting lasers.
关键词： AlOx,oxidation,anisotropy,VCSEL
更新于2025-09-11 14:15:04
-
Polarization-resolved and polarization- multiplexed spike encoding properties in photonic neuron based on VCSEL-SA
摘要： The spike encoding properties of two polarization-resolved modes in vertical-cavity surface-emitting laser with an embedded saturable absorber (VCSEL-SA) are investigated numerically, based on the spin-flip model combined with the Yamada model. The results show that the external input optical pulse (EIOP) can be encoded into spikes in X-polarization (XP) mode, Y-polarization (YP) mode, or both XP and YP modes. Furthermore, the numerical bifurcation diagrams show that a lower (higher) strength of EIOP is beneficial for generating tonic (phasic) spikes; a small amplitude anisotropy contributes to wide (narrow) tonic spiking range in XP (YP) mode; a large current leads to low thresholds of EIOP strength for both XP and YP modes. However, the spike encoding properties are hardly affected by the phase anisotropy. The encoding rate is shown to be improved by increasing EIOP strength. Moreover, dual-channel polarization-multiplexed spike encoding can also be achieved in a single VCSEL-SA. To the best of our knowledge, such single channel polarization-resolved and dual-channel polarization-multiplexed spike encoding schemes have not yet been reported. Hence, this work is valuable for ultrafast photonic neuromorphic systems and brain-inspired information processing.
关键词： VCSEL-SA,spike encoding,neuromorphic systems,polarization-resolved modes,brain-inspired information processing
更新于2025-09-10 09:29:36