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Abstrak :
ABSTRAK
Divais directional coupler dan optical switch merupakan komponen yang dibutuhkan dalam pemrosesan sinyal optik. Kemajuan teknologi wavelength division multiplexing (WDM) dan pertumbuhan lalu lintas internet yang cepat memicu banyak penelitian tentang teknologi switching optik. Galium Nitrida (GaN) merupakan material semikonduktor nitrida kelompok III yang menjadi kandidat menjanjikan untuk divais yang beroperasi pada panjang gelombang komunikasi optik. Pada penelitian ini dilakukan desain directional coupler dan optical switch menggunakan material GaN untuk panjang gelombang telekomunikasi, yaitu 1,55 um. Desain directional coupler terdiri dari pandu gelombang S-bend dan linear sedangkan desain optical switch berbasis Mach-Zehnder Interferometer yang terdiri dari dua directional coupler yang dihubungkan dengan dua lengan persegi panjang. Optimasi desain dilakukan dengan metode finite difference beam propagation method (FD-BPM) menggunakan perangkat lunak OptiBPM. Optimasi dilakukan dengan memvariasikan parameter pandu gelombang meliputi lebar, ketebalan, width gap dan coupling gap. Dari hasil simulasi ditunjukkan bahwa lebar dan tebal terbaik untuk memperoleh propagasi single mode masing-masing adalah 4 um. Selanjutnya, berdasarkan hasil optimasi ukuran pandu gelombang dilakukan desain directional coupler dan optical switch. Ditunjukan bahwa directional coupler dengan panjang 980 um dan lebar 15 um dengan width gap 7 um dan coupling gap 6 μm menghasilkan daya keluaran sebesar 91,71% dengan splitting ratio sebesar 48,83% : 48,03%, excess loss dan power imbalance berturut-turut sebesar 0,37 dB dan 0,07 dB. Tahap selanjutnya, berdasarkan lebar dan tebal pandu gelombang, dilakukan optimasi desain optical switch. Dari hasil eksperimen numerik ditunjukkan bahwa desain optical switch terbaik, memiliki panjang 6380 μm dan lebar 15 um, dengan panjang elektroda sebesar 4500 μm. Optical switch mampu beroperasi sebagai switch pada
 = 34 V dengan insertion loss dan extinction ratio berturut-turut sebesar 1,23 dB dan 8,46 dB

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ABSTRACT
Directional coupler and optical switches are the components needed in optical signal processing. The progress of wavelength division multiplexing (WDM) technology and the rapid growth of internet traffic have triggered much research regarding optical switching technology. Gallium Nitride (GaN) is a III-nitride semiconductor becomes a promising candidate for devices which operate in wavelength optical communications. In this research, the design of GaN-based directional coupler and optical switch design was conducted for telecommunication wavelength at 1.55 um. The design of directional coupler consists of S-bend and linear waveguide, whereas, design of optical switch based on Mach-Zehnder Interferometer consists of two directional couplers connected by two rectangular arms. Design optimization was conducted by finite difference beam propagation method (FD-BPM) using OptiBPM software. Optimization was conducted by a varying waveguide parameter such as waveguide width, waveguide thickness, width gap and coupling gap. From the simulation results, the best of width and thickness were 4 um and 4 um, respectively, for support single-mode propagation. Next, based on the optimization result of the waveguide dimension, it was conducted a design of the directional coupler and optical switch. It was noticed that the directional coupler was 980 m long, and 15 um wide with width gap and coupling gap were 7 um and 6 μm, respectively. It generated the output power of 91.71% with the splitting ratio of 48.83 %: 48.03% while the excess loss of 0.37 dB and the power imbalances of 0.07 dB. The next step, optimization of the optical switch design was conducted based on the width and thickness of the waveguide. From the simulation result, the best design of the optical switch was 6380 μm long and 15 um wide, with the electrode length was 4500 μm. The optical switch could operate as an optical switch at = 34V with an insertion loss of 1.23 dB and an extinction ratio of 8.46 dB.

Abstrak :
This book offers the reader a practical guide to the control and characterization of laser diode beams. Following a short introduction to the working principles of laser diodes, the book describes the basics of laser diode beams and beam propagation, including Zemax modeling of a Gaussian beam propagating through a lens. The core of the book is concerned with laser diode beam manipulations, collimating and focusing, circularization and astigmatism correction, coupling into a single mode optical fiber, diffractive optics and beam shaping, and manipulation of multi transverse mode beams. The final chapter of the book covers beam characterization methods, describing the measurement of spatial and spectral properties, including wavelength and linewidth measurement techniques.

Abstrak :
The PUILS series delivers up-to-date reviews of progress in Ultrafast Intense Laser Science, a newly emerging interdisciplinary research field spanning atomic and molecular physics, molecular science and optical science which has been stimulated by the recent developments in ultrafast laser technologies. Each volume compiles peer-reviewed articles authored by researchers at the forefront of each their own subfields of UILS. These are followed by reports of cutting-edge discoveries. This eighth volume covers a broad range of topics from this interdisciplinary research field, focusing on molecules interacting with ultrashort and intense laser fields, advanced technologies for the characterization of ultrashort laser pulses and their applications, laser plasma formation and laser acceleration.

Abstrak :
Nonlinear photonics and novel optical phenomena contains contributed chapters from leading experts in nonlinear optics and photonics, and provides a comprehensive survey of fundamental concepts as well as hot topics in current research on nonlinear optical waves and related novel phenomena. The book covers self-accelerating airy beams, integrated photonics based on high index doped-silica glass, linear and nonlinear spatial beam dynamics in photonic lattices and waveguide arrays, the theory of polariton solitons in semiconductor microcavities, and terahertz waves.

Abstrak :
Recent state-of-the-art technologies in fabricating low-loss optical and mechanical components have significantly motivated the study of quantum-limited measurements with optomechanical devices. Such research is the main subject of this thesis. In the first part, the author considers various approaches for surpassing the standard quantum limit for force measurements. In the second part, the author proposes different experimental protocols for using optomechanical interactions to explore quantum behaviors of macroscopic mechanical objects. Even though this thesis mostly focuses on large-scale laser interferometer gravitational-wave detectors and related experiments, the general approaches apply equally well for studying small-scale optomechanical devices.

Abstrak :
Recent technological breakthrough in the field of Terahertz radiation has triggered new applications in biology and biomedicine. Particularly, biological applications are based on the specific spectroscopic fingerprints of biological matter in this spectral region. Historically with the discovery of new electromagnetic wave spectrum, we have always discovered new medical diagnostic imaging systems. The use of terahertz wave was not realized due to the absence of useful terahertz sources. Now after successful generation of THz waves, it is reported that a great potential for THz wave exists for its resonance with bio-molecules. There are many challenging issues such as development of THz passive and active instrumentations, understanding of THz-Bio interaction for THz spectroscopy, THz-Bio nonlinear phenomena and safety guideline, and THz imaging systems. Eventually the deeper understanding of THz-Bio interaction and novel THz systems enable us to develop powerful THz biomedical imaging systems which can contribute to biomedical industry. This is a truly interdisciplinary field and convergence technology where the communication between different disciplines is the most challenging issue for the success of the great works.

Abstrak :
Heterogeneous integration uses packaging technology to integrate dissimilar chips, LED, MEMS, VCSEL, etc. from different fabless houses and with different functions and wafer sizes into a single system or subsystem. How are these dissimilar chips and optical components supposed to talk to each other? The answer is redistribution layers (RDLs). This book addresses the fabrication of RDLs for heterogeneous integrations, and especially focuses on RDLs on: A) organic substrates, B) silicon substrates (through-silicon via (TSV)-interposers), C) silicon substrates (bridges), D) fan-out substrates, and E) ASIC, memory, LED, MEMS, and VCSEL systems. The book offers a valuable asset for researchers, engineers, and graduate students in the fields of semiconductor packaging, materials sciences, mechanical engineering, electronic engineering, telecommunications, networking, etc.