Silicon photonic polarimeters and spectropolarimeters

Puisqu’ils offrent la possibilité d’intégrer monolithiquement un grand nombre de composants à un faible coût, les circuits intégrés photoniques (CIPs) sont devenus une plateforme de choix pour la réalisation de capteurs optiques sur puce. Cette thèse propose, puis démontre l’utilisation de CIPs sur silicium pour la réalisation de polarimètres et de spectro-polarimètres sur puce. Dans le premier chapitre, nous présentons un séparateur de polarisation utilisant un réseau de nano-antennes en forme d’arêtes de poisson sur silicium. Nous montrons également qu’une structure de la sorte est en mesure de séparer deux états de polarisation arbitraires qui sontorthogonaux entre-eux. De plus, nous avons amélioré le précédent modèle théorique existant pour y inclure ce phénomène. Dans le second chapitre, nous présentons et démontrons de façon expérimentale un polarimètre intégré sur silicium qui requiert 6 photodétecteurs (6-PDs). Ici, la structure optimale veut dire que, pour un niveau de bruit donné, cette structure permet d’obtenir l’état de polarisation avec la précision la plus élevée. Nous démontrons également de façon théorique que cette configuration proposée peut maintenir un état optimal sur une plage de longueur d’onde de100 nm. Dans le troisième chapitre, nous proposons une jonction en « Y » paramétrisée dont le ratio de séparation de puissance peut être choisi avant la fabrication, lors de la conception. Sur une plage de longueur d’onde de 100 nm, les pertes de puissance de la jonction sont inférieuresà 0.36 dB, et ce, pour tout ratio arbitraire de séparation de puissance. De plus, sa taille de1.4 µm × 2.3 µm le rend très compact.Au chapitre 4, nous proposons un polarimètre optimal composé de quatre photodétecteurs(4-PDs) possédant ces propriétés à partir de la jonction en « Y » proposée au chapitre 3. Un polarimètre non-optimal est fabriqué de manière à montrer la différence entre celui-ci et le cas optimal. Les résultats expérimentaux montrent que l’erreur de reconstruction du composant optimal est inférieure de 44 % à celle du composant non-optimal.Dans le cinquième chapitre, nous proposons et faisons la démonstration d’un spectro- polarimètre réalisé intégralement sur puce. Afin de permettre une analyse spectro-polarimétrique iiicomplete, quatre micro-résonateurs à effet Vernier compacts sont intégrés monolithiquement avec un polarimètre large-bande. Le composant optique proposé offre une solution de spectropolarimétrie sur semi-conducteur tout en gardant une taille très compacte de 1 × 0.6 mm2et une faible consommation de puissance de 360 mW. La détection spectrale pour tous les composants de Stokes est démontrée sur une large plage de longueur d’onde de 50 nm, et ce avec une résolution de 1 nm par la caractérisation d’un matériau possédant une chiralité structurelle.The ability to monolithically integrate numerous components in low-cost, photonic integratedcircuits (PICs) has become a hot topic in the research for realizing on-chip optical measurement. In this thesis, we propose and demonstrate two on-chip polarimeters and an on-chipspectropolarimeter using silicon PICs.In the first chapter, we investigate the optical properties of the silicon fishbone nanoantennaarray. We found that this type of structure can be used to identify any two arbitrary orthogonalpolarization states. The previous theoretical model was also improved upon in order to explainthis phenomenon.In the second chapter, we propose and experimentally demonstrate a silicon polarimeter whichrequires six photodetectors. We also theoretically demonstrate that the proposed configurationcan maintain an optimal state over a wavelength range of 100 nm. Here, the optimal structuremeans that for a given noise, the structure would allow for the highest and polarizationindependent accuracy of the polarization state measurement to be obtained.In the third chapter, we propose a parameterized Y-junction whose arbitrary power splittingratio can be selected in layout design. For an arbitrary power splitting ratio, its excess losscan keep below 0.36 dB over a wavelength range of 100 nm. Moreover, this device has anultra-compact footprint of 1.4 µm × 2.3 µm.Based on the Y-junction proposed in chapter 3, the fourth chapter proposes an optimal siliconphotonic polarimeter that only requires four photodetectors and its configuration is optimal.A non-optimal device is fabricated to show the difference between optimal and non-optimaldevices. The experimental results indicate that the reconstructed error of the optimal deviceis 44% lower than that of the nonoptimal device.In the fifth chapter, a completely chip-level spectropolarimeter is proposed. Four compactVernier microresonator spectrometers are monolithically integrated with a broadband polarimeter to achieve full-Stokes spectropolarimetric analysis. The proposed device offers asolid-state spectropolarimetry solution with a small footprint of 1 × 0.6 mm2 and low powerconsumption of 360 mW. Full-Stokes spectral detection across a broad spectral range of 50 nmwith a resolution of 1 nm is demonstrated in characterizing a material that possesses structuralvchirality

The 1st Advanced Manufacturing Student Conference (AMSC21) Chemnitz, Germany 15–16 July 2021

The Advanced Manufacturing Student Conference (AMSC) represents an educational format designed to foster the acquisition and application of skills related to Research Methods in Engineering Sciences. Participating students are required to write and submit a conference paper and are given the opportunity to present their findings at the conference. The AMSC provides a tremendous opportunity for participants to practice critical skills associated with scientific publication. Conference Proceedings of the conference will benefit readers by providing updates on critical topics and recent progress in the advanced manufacturing engineering and technologies and, at the same time, will aid the transfer of valuable knowledge to the next generation of academics and practitioners. *** The first AMSC Conference Proceeding (AMSC21) addressed the following topics: Advances in “classical” Manufacturing Technologies, Technology and Application of Additive Manufacturing, Digitalization of Industrial Production (Industry 4.0), Advances in the field of Cyber-Physical Systems, Virtual and Augmented Reality Technologies throughout the entire product Life Cycle, Human-machine-environment interaction and Management and life cycle assessment.:- Advances in “classical” Manufacturing Technologies - Technology and Application of Additive Manufacturing - Digitalization of Industrial Production (Industry 4.0) - Advances in the field of Cyber-Physical Systems - Virtual and Augmented Reality Technologies throughout the entire product Life Cycle - Human-machine-environment interaction - Management and life cycle assessmen

Nanofibers - production, properties and functional applications

With the rapid development of nanoscience and nanotechnology over the last decades, great progress has been made not only in the preparation and characterization of nanomaterials, but also in their functional applications. As an important one-dimensional nanomaterial, nanofibers have extremely high specific surface area because of their small diameters, and nanofiber membranes are highly porous with excellent pore interconnectivity. These unique characteristics plus the functionalities from the materials themselves impart nanofibers with a number of novel properties for applications in areas as various as biomedical engineering, wound healing, drug delivery and release control, catalyst and enzyme carriers, filtration, environment protection, composite reinforcement, sensors, optics, energy harvest and storage , and many others. More and more emphasis has recently been placed on large-scale nanofiber production, the key technology to the wide usages of nanofibers in practice. Tremendous efforts have been made on producing nanofibers from special materials. Concerns have been raised to the safety issue of nanofibrous materials. This book is a compilation of contributions made by experts who specialize in their chosen field. It is grouped into three sections composed of twenty-one chapters, providing an up-to-date coverage of nanofiber preparation, properties and functional applications. I am deeply appreciative of all the authors and have no doubt that their contribution will be a useful resource of anyone associated with the discipline of nanofibers

Performance Analysis For Wireless G (IEEE 802.11 G) And Wireless N (IEEE 802.11 N) In Outdoor Environment

This paper described an analysis the different capabilities and limitation of both IEEE technologies that has been utilized for data transmission directed to mobile device. In this work, we have compared an IEEE 802.11/g/n outdoor environment to know what technology is better. the comparison consider on coverage area (mobility), through put and measuring the interferences. The work presented here is to help the researchers to select the best technology depending of their deploying case, and investigate the best variant for outdoor. The tool used is Iperf software which is to measure the data transmission performance of IEEE 802.11n and IEEE 802.11g

Performance analysis for wireless G (IEEE 802.11G) and wireless N (IEEE 802.11N) in outdoor environment

This paper described an analysis the different capabilities and limitation of both IEEE technologies that has been utilized for data transmission directed to mobile device. In this work, we have compared an IEEE 802.11/g/n outdoor environment to know what technology is better. The comparison consider on coverage area (mobility), throughput and measuring the interferences. The work presented here is to help the researchers to select the best technology depending of their deploying case, and investigate the best variant for outdoor. The tool used is Iperf software which is to measure the data transmission performance of IEEE 802.11n and IEEE 802.11g

Integrated Planar Optical Devices Based on Silicon Nitride Waveguides

Silicon nitride is a subject of growing interest with the potential of delivering planar integrated optical devices as a complementary part of silicon photonics. The material has a moderate refractive index, wide optical transparency window, lack of two-photon absorption, and low nonlinear susceptibility. Thanks to its CMOS fabrication compatibility, the freedom of integrating different materials into Si3N4 renders the platform omnipotent. This dissertation is dedicated to developing Si3N4 based optical devices integrated with Si nanowires, fishbone antennas, bowtie antennas and gold nanoparticles to achieve active and passive optical functionalities. To be specific, the thesis covers Si3N4 based optical leaky wave antennas that emit narrow beams towards desired directions in free space, bimetallic fishbone waveguide-based detectors that detect optical radiations plasmonically and thermo-mechanically, and trench waveguides that can be equipped with bowtie antennas for optical trapping or with gold nanoparticles for nonlinearity enhancement.The purpose of the first part of the dissertation is to experimentally demonstrate emission from a leaky wave antenna and to investigate the possible modulation method in tuning the radiation beam. The optical leaky wave antenna is composed of a Si3N4 waveguide and periodic Si nanowires. The antenna has a single directive radiation peak at the angle of 85.1° in the measured range from 65° to 112° at the wavelength of 1550 nm. The side lobes are at least 7 dB lower than the main peak. The peak radiation angle moves to the broad side as the wavelength increases. The device can find promising applications in optical communications, especially for multi-wavelength space division multiplexing owing to its capability of beam scanning with frequency. The study on the optical leaky wave antenna proves the functionality of off-plane emission from a waveguide and explores the potential electronic modulation methods.The second part of the dissertation presents a plasmo-thermomechanical radiation detector. The goal of the second work is to investigate if thermomechanical vibrations can be detected in an on-chip optical readout system. To study the problem, I designed a device that is composed of a Si3N4 waveguide and 13 fishbone nanowires suspended above the waveguide. Each wire is 12.54 µm long and consists of 16 nanoantennas with a period of 660 nm. Under the illumination of 660 nm light, the detector shows a responsivity of 3.954×10-3 µm2/µW. The noise equivalent power, dominated by the waveguide coupling instability, is 3.01 µW/√Hz. The 3dB bandwidth of the device is 9.6 Hz corresponding to a time constant of 16.6 ms. Besides the demonstrated radiation detector for visible wavelength, another device for mid-infrared wavelength has also been designed and optimized for fabrication. This study verifies the possibility of using on-chip waveguide-based readout system to detect the mechanical vibration that is induced by radiation.The third part of the dissertation focuses on Si3N4 trench waveguides. The objective of this part is to thoroughly explore the optical properties of the trench waveguides and investigate their applications. The trench waveguide shape is determined by the silicon wet etching properties and thus can be controlled in either triangle or trapezoidal shape. Experimental results show that the propagation loss of the TM mode can be as low as 0.8 dB/cm. The nonlinear parameter of the waveguide is measured to be 0.3 W-1/m. Coating gold nanoparticles can enhance the waveguide nonlinearity. The trench waveguide is promising for liquid sensing thanks to its unique structure that can combine fluidic channel and waveguide together. Explorations on the trapezoidal trench waveguide and bowtie antennas also show that the platform is suitable for trapping nanoparticles. Switching between trapping and releasing the particles can be done by changing the mode polarization states from the TE mode to the TM mode. This work provides an in-depth study of the trench waveguides from optical properties, fabrication, to applications.This study expands the knowledge and capabilities of conventional silicon photonics and paves way for novel devices pertinent to communications and sensing. In particular, this thesis shows that the use of Si3N4 based planar optical circuits, the operational bandwidth of silicon photonics can cover wavelengths shorter than 1.1μm for novel applications. The presented work on new optical planar emitters, waveguides, detectors, optical trapping, and microfluidics at wavelengths from visible to mid-wave infrared will be beneficial to both future research and industry applications

Integrated Planar Optical Devices Based on Silicon Nitride Waveguides

Silicon nitride is a subject of growing interest with the potential of delivering planar integrated optical devices as a complementary part of silicon photonics. The material has a moderate refractive index, wide optical transparency window, lack of two-photon absorption, and low nonlinear susceptibility. Thanks to its CMOS fabrication compatibility, the freedom of integrating different materials into Si3N4 renders the platform omnipotent. This dissertation is dedicated to developing Si3N4 based optical devices integrated with Si nanowires, fishbone antennas, bowtie antennas and gold nanoparticles to achieve active and passive optical functionalities. To be specific, the thesis covers Si3N4 based optical leaky wave antennas that emit narrow beams towards desired directions in free space, bimetallic fishbone waveguide-based detectors that detect optical radiations plasmonically and thermo-mechanically, and trench waveguides that can be equipped with bowtie antennas for optical trapping or with gold nanoparticles for nonlinearity enhancement.The purpose of the first part of the dissertation is to experimentally demonstrate emission from a leaky wave antenna and to investigate the possible modulation method in tuning the radiation beam. The optical leaky wave antenna is composed of a Si3N4 waveguide and periodic Si nanowires. The antenna has a single directive radiation peak at the angle of 85.1° in the measured range from 65° to 112° at the wavelength of 1550 nm. The side lobes are at least 7 dB lower than the main peak. The peak radiation angle moves to the broad side as the wavelength increases. The device can find promising applications in optical communications, especially for multi-wavelength space division multiplexing owing to its capability of beam scanning with frequency. The study on the optical leaky wave antenna proves the functionality of off-plane emission from a waveguide and explores the potential electronic modulation methods.The second part of the dissertation presents a plasmo-thermomechanical radiation detector. The goal of the second work is to investigate if thermomechanical vibrations can be detected in an on-chip optical readout system. To study the problem, I designed a device that is composed of a Si3N4 waveguide and 13 fishbone nanowires suspended above the waveguide. Each wire is 12.54 µm long and consists of 16 nanoantennas with a period of 660 nm. Under the illumination of 660 nm light, the detector shows a responsivity of 3.954×10-3 µm2/µW. The noise equivalent power, dominated by the waveguide coupling instability, is 3.01 µW/√Hz. The 3dB bandwidth of the device is 9.6 Hz corresponding to a time constant of 16.6 ms. Besides the demonstrated radiation detector for visible wavelength, another device for mid-infrared wavelength has also been designed and optimized for fabrication. This study verifies the possibility of using on-chip waveguide-based readout system to detect the mechanical vibration that is induced by radiation.The third part of the dissertation focuses on Si3N4 trench waveguides. The objective of this part is to thoroughly explore the optical properties of the trench waveguides and investigate their applications. The trench waveguide shape is determined by the silicon wet etching properties and thus can be controlled in either triangle or trapezoidal shape. Experimental results show that the propagation loss of the TM mode can be as low as 0.8 dB/cm. The nonlinear parameter of the waveguide is measured to be 0.3 W-1/m. Coating gold nanoparticles can enhance the waveguide nonlinearity. The trench waveguide is promising for liquid sensing thanks to its unique structure that can combine fluidic channel and waveguide together. Explorations on the trapezoidal trench waveguide and bowtie antennas also show that the platform is suitable for trapping nanoparticles. Switching between trapping and releasing the particles can be done by changing the mode polarization states from the TE mode to the TM mode. This work provides an in-depth study of the trench waveguides from optical properties, fabrication, to applications.This study expands the knowledge and capabilities of conventional silicon photonics and paves way for novel devices pertinent to communications and sensing. In particular, this thesis shows that the use of Si3N4 based planar optical circuits, the operational bandwidth of silicon photonics can cover wavelengths shorter than 1.1μm for novel applications. The presented work on new optical planar emitters, waveguides, detectors, optical trapping, and microfluidics at wavelengths from visible to mid-wave infrared will be beneficial to both future research and industry applications