This PDF file contains the front matter associated with SPIE Proceedings Volume 11193, including the Title Page, Copyright information, Table of Contents, Author and Conference Committee lists.

A spontaneous formation of SiGe is reported, which is induced at mesa sidewalls of Si-capped Ge epitaxial layers selectively grown on Si. Ultrahigh-vacuum chemical vapor deposition is used to grow Ge mesa stripes on (001) Si wafers partially covered with SiO2 masks, followed by a growth of Si capping layer. Micro-Raman spectra reveals that SiGe is formed selectively on the {113} sidewalls of Ge mesa structure running in the [110] direction, resulting from an intermixing between the Si capping and Ge layers, whereas no such SiGe is detected on the flat-top (001) mesa surface. An increased amount of SiGe is observed for stripe patterns misaligned from the [110] direction. This suggests that the atomic step/roughness on the sidewall contributes to the intermixing. The observed SiGe formation would be applied to the bandgap engineering to tune the operation wavelengths in Ge photonic devices on Si. In fact, a significant blue shift in the direct-gap light emission peak is observed for submicron-wide Ge mesa structures with no flat-top (001) surface, where the surface is totally surrounded by SiGe.

In this paper, a grating assisted MDM-PDM hybrid (de)multiplexer based on the silicon-on-insulator (SOI) platform has been proposed and analyzed using coupled mode theory with effective index method (EIM). The proposed device consists of a multimode wide waveguide and five single mode narrow waveguides. The quasi- TE/TM modes of the wide waveguide are phase matched with the respective contra-propagating fundamental quasi-TE/TM modes of the single mode narrow waveguides. The phase matching conditions are satisfied by using different period gratings, which are surface corrugated on the wide waveguide. The proposed device structure exhibits good crosstalk, insertion loss, and return loss values.

We show that whispering gallery modes on the surface of optical fibers can be reflected from the optical fiber facet. Due to reflection, a locking effect occurs near the optical fiber facet for the whispering gallery modes with an axial component of the wave vector. We obtained an analytical expression for determining the resonant wavelengths. We also experimentally measured the phase velocity of the optical pulse propagating in whispering gallery modes and reflecting from the fiber facet.

Using the new classical spiraling photon model proposed by Hongrui Li, the features of light involving reflection, refraction, polarization, total reflection, evanescent wave, and Goos-Hanchen shift can be clearly elucidated, and the distinct boundary of the evanescent wave can be observed. The evanescent wave is neither exponential decay along z direction nor goes along x direction infinitely. As of now, the explanation of interference and diffraction of light remains unsolved by our spiraling photon model. Herein we use this model to illustrate the diffraction and interference of light, diffraction at a straight edge and the origin of the spiraling force of photons. Moreover, we show new evidences that are contrary to the wave theory of light generated by our experiments. In other words, the incorrectness of Huygens-Fresnel diffraction theory is found. Therefore we believe that the feature of light is not an electromagnetic wave.

This paper analyzes a germanium-doped silicon traveling wave Mach-Zehnder modulator (TWMZM) for high speed operation at 1550 nm wavelength. Single arm drive modulator performance using non-return-to-zero on-off keying (NRZ-OOK) driving scheme has been investigated. The phase-loss characteristics of the graded-index silicon-germanium PN phase shifter have been determined numerically. The traveling wave electrode has been designed for 1.5 mm long phase shifter. The 3 dB modulation bandwidth of the designed TWMZM is calculated to be 31 GHz at -2 V and an error-free operation of 59 Gbps has been obtained for 2 V peak-to-peak drive voltage with an extinction of ~6 dB.

Femtosecond laser has the feature of ultra-short and ultra-fast. In recent years, femtosecond laser has been used extensively in the field of new energy, automobiles, large aircraft, and biomedical fields. The femtosecond laser induced surface structure has the advantages of simple process, fast processing speed and high fineness, and it is one of the most widely used surface structure preparation method. Femtosecond laser induced surface periodic structures have wide range of applications in many areas, such as hydrophobic surface or hydrophilic surface, color effect, surface-enhanced Raman scattering(SERS), and so on. Inspired by micro-nanostructures with unique functions on various of biological surfaces in nature, researchers use femtosecond laser micro-nanofabrication produce technology to prepare controlled periodic micro-nano structures on metals, dielectrics, and semiconductor surfaces. Thus playing a role in improving the surface properties of metals. For example, butterflies and birds have very beautiful colors, superhydrophobicty of lotus leaves, shark skin can reduce frictional resistance, strong adsorption capacity of gecko claws, and so on. The improvement of material surface properties can bring about the realization of new functions and the development of related technology, it can effectively serve the production and life of human beings. This article introduces the development and research status of the surface periodic structure induced by femtosecond laser, and discusses the influence of materials, laser pulse parameters, processing methods and processing environment on the surface periodic structure. The application prospect of femtosecond laser induced surface periodic structure are pointed out, and the challenges it faces at present stage are summarized.

CsPbI_xBr_1-x thin film with spontaneous polarization can be made into the self-powered photodetector based on light induced pyroelectric effect. It can perform without an external power source to meet the demands of the portable and wearable nanodevices. Here, a novel self-powered photodetector based on all-inorganic halide perovskites CsPbI_xBr_1-x thin film is fabricated, which shows an ultrafast response speed of less than 6μs under the laser illumination at zero bias. Also, the response characteristics of the self-powered photodetector from UV to near infrared are experimented and exhibited. Especially, the device has a higher response to 405nm UV light than other. This work extends the potential applications of perovskites in energy scavenging and self-powered sensor systems.

In this work we design a wire grid polarizer(WGP) with silver nanowire grids on a germanium(Ge) substrate with 550nm period and 200nm thickness double-layer and single-layer wire grids based on FDTD method, which can achieve an average TM transmittance(TMT) over 70% and 48% and an extinction ratio(ER) over 76dB and 32dB respectively in the range of 3~15μm waveband. The photoresist grating was made by the Lloyd’s mirror interferometer interference lithography (IL) systems and the metal silver was deposited by thermal evaporation, which avoid the high cost of electron beam lithography and the difficult process of wet etching or dry etching. The fabrication shows that method is proved to be easy implement in the fabrication of sub-wavelength metal gratings. The experiment results show the polarizer has uniform polarization characteristics in the wide infrared band that the average TMT and ER of the doublelayer polarizer are 72.6% and 27.5dB in 3~15μm with single side antireflection coating. The average TMT and ER of the single-layer polarizer are 59.1% and 25.1dB in 3~15μm.

This paper describes detailed study of photoprocesses in bovine serum albumin, silver nanoparticles and Rhodamine 6G (R6G) dye complexes using plasmon-enhanced fluorescence effect. Fluorescence spectroscopy analysis of bovine serum albumin molecules in systems doped with silver nanoparticles and rhodamine 6G has been performed. The perspectives of plasmon-controlled photoprocesses in the model complexes for applications of modern physics and biophotonics were shown. Investigations both tryptophan and tyrosine fluorescence of BSA in the complex has been investigated. Experimental concentrations of protein, dye and nanoparticles at which a stable plasmon-enhanced fluorescence effect was observed. Results of the study can be applied for labeling and configuring drug delivery systems for investigation of small blood components investigation such as platelets.

Silicon photonics uses mature CMOS industry to design, manufacture and package photonic devices. It can break through the limitation of existing electrical technology in terms of cost, power consumption and integration, to meet the needs for future development of communication, data center, LiDAR, biosensor, quantum computing, etc. Although silicon photonics process is based on CMOS technology and facilities, a mature CMOS platform can not be seamlessly transformed into a silicon photonics platform, because there are great differences in device types and graphic characteristics between photonics and electrical integrated circuits. The key challenges and solutions in developing a manufacturable photonic technology were described in this paper. According to the difference of manufacturing process, a series of process modules for silicon photonics were developed on 200-mm CMOS platform, such as silicon deep-etch process for edge-coupling technology. An abundant device library for process design kit was established, including stripe waveguide, rib waveguide, grating coupler, MMI, directional coupling, waveguide crossing, AWG, MZ modulator, and photodetector. Meanwhile, Si₃N₄ material is also one of the important materials for future development of photonic integration. Through process optimization, the propagation loss of Si3N4 waveguide were approximately 0.2 dB/cm with thickness of 100 nm and 0.6 dB/cm with thickness of 400 nm, respectively. Automated wafer-level optical test was used to enable statistical photonic device characterization for development, photonic modeling, and manufacturing controls.

Spin-controlled vortex generation is a manifestation of the spin-orbit interaction (SOI) of light, which has been extensively studied in Pancharatnam-Berry geometric phase elements in recent years. The SOI under the normal incidence of a light beam at a sharp interface, also shown by a spin-dependent vortex, has attracted little attention, except for a few exceptions. Here, we establish a Fresnel Jones matrix to fully describe the dynamics of beam reflection and refraction at sharp interfaces under normal incidence. It is pointed out that the vortex phase originates from the topological structure of the beam itself and is essentially a spin-redirection Berry phase. Although the geometric phase in Pancharatnam-Berry elements comes from the anisotropy of the external material, which shows a fundamental difference, they are the same in form. We then give a comparative study of the two kinds of SOI, and reveal the intrinsic connection and difference between them. Our research not only establishes a unified framework to describe the two SOIs, but also offers a new perspective for studying the SOIs in other physics.

In this paper we demonstrate a branched Rutile TiO₂ nanorod structure which used as a model architecture for efficient photoelectrochemical devices for simultaneously offers a large contact area with the electrolyte, excellent lighttrapping characteristics, and a highly conductive pathway for charge carrier collection. We developed a facile hydrothermal synthesis method to achieve rutile TiO₂ nanorod arrays on FTO substrate without use of any acid. The morphology of nanorods can be finely tuned by changing the growth parameters, and the potential of the as-made rutile TiO₂ nanorods in perovskite solar cells was evaluated, showing power conversion efficiency up to 11.1%.

We propose for the first time a new method to electronically control the cavity length of mode-locked fibre lasers, allowing different lasing conditions and performance in a single laser configuration. A special cavity design was developed that combines a multi-kilometre fibre resonator boosting pulse energy to hundreds nJ with an all-PM fibre resonator providing nearly 200-m long environmentally-stable cavity round trip. Switching between the cavities is achieved automatically by adjusting modulation frequency of an optical switcher (used for active mode locking) to match the cavity round-trip time of one of the cavities. We discuss details of our method, its possibilities and limitations, in particular related to stability of pulse parameters.

We fabricated a polydimethylsiloxane (PDMS)-coated silica microbubble cavity with rich whispering gallery modes (WGMs). An electromagnetically induced transparency (EIT) window is realized through experimentally coupling a tapered fiber with the PDMS-coated microbubble resonator (MBR). There is a high-Q mode in the vicinity of a low-Q mode in transmission spectra. The experimental results prove that the high-Q mode performs a small redshift while the low-Q mode performs a large blueshift when the input power increases. This attributes to the negative thermo-optical coefficient (TOC) of PDMS and the positive TOC of silica. An EIT-like window is realized when these two modes are on-resonance with same frequency.

Nano-conglutination technology is a nonconventional nanofabrication technique to use adhesive materials to “stick” nanostructures, which relies on excellent properties of adhesive materials. In this article, we propose a novel hybrid material based on thiol-ene system as the adhesive material for nano-conglutination technology. Thiol-ene system is a kind of UV-curable polymer via “click reaction” to form cross-linked network, which is low viscosity, rapid polymerization rate, high Young’s modulus, and low cost. High-resolution nanostructures such as nano-bowl and nanopillar arrays with sub-200 nm resolution are achieved using thiol-ene adhesive material via nano-conglutination technology. Special reactions of thiols with reactive carbon-carbon double bonds happen in the crosslink process, which make the thiol-ene system be enough low viscosity to keep conformal with the stuck nanostructures and be enough high rigid to easily separate from the mold and keep the original arrangement of nanostructures. This study promotes nanostructures for potential applications of optical, electronics, and photonic devices due to the surface plasmon resonance, surface enhanced Raman spectroscopy, electrical effect, and nonlinear optical response.

Raman lasing has been realized in different kinds of whispering gallery mode microresonators because of its high quality factors and relatively small mode volumes. The non-linear coefficient of carbon disulfide is much larger than that of silicon dioxide. In this paper, we fabricate a high quality factor silica microbubble resonator. In addition, we report on the realization of Raman lasing in an empty silica microbubble resonator. Moreover, Raman lasing in carbon disulfide filled optofluidic microbubble resonator at pump wavelengths of 950 nm is also implemented.