28 research outputs found
Micro-structured ferroelectric superlattice for efficient acousto-optic devices
In this thesis we have investigated and proposed acoustic superLattices (ASLs) made of periodically poled ZX-cut lithium niobate (PPLN) associated ith coplanar electrodes as an effective alternative for surface acoustic wave (SAW) generation. In order to examine the acoustic transduction in the SL transducer we have developed and employed two modeling techniques. i.e . scalar approximation and finite element method (FEM) analysis (2-D nd 3-D modeling) implemented in COMSOL MULTIPHYSICS. Both techniques give similar results with respect to the characteristics of generated
SAW modes. The calculated results obtained with the 3-D FEM simulation confirmed the Rayleigh nature of the generated SAW, showing that the
excited SAW in the ASL is similar to that of the standard interdigitated transducer (IDT). From the propagation analysis in 2-D FEM simulation. we obtained that in addition to the SAW, the ASL transducer excites longitudinal bulk acoustic wave (L-BAW). Moreover. the 2-D model showed that the
SAW excited by the ASL transducer does not propagate but it is rather confined within the transducer.
Several ASL transducers, with different lattice periods, have been realized and characterized, also to validate the modeling and design tools . One and two-portelectrical measurements have been performed to evaluate the electro-acoustic response. In addition laser interferome try has been carried out o determine the out-of-plane component of the SAW displacement. With respect to the standard IDT configuration using the same crystal orientation, he efficiency of the SAW generation in the proposed designs is similar, while, for the same grating period, the resonance frequency that can be achieved is two times larger. In addition to the SAW, unlike its lOT counterparts, the ASL transducer can excite the L-BAW, as it had been predicted by the modeling. The two-port measurements have shown that the SAW signal collected at the receiver is small, indicating that the SAW energy remains essentially confined within the transmitter. This experimental result too is in agreement with the aforementioned theoretical predictions.
After the experimental validation of the modeling, we designed and fabricated acousto-optic (AO) filters incorporating the ASL transducer. ASL struc tures with 20 tm period and coplanar electrodes have been realized along with 6 m wide Ti-LiNb03 optical channel waveguide. In that way monolithic and integrated (waveguide) SAW based AO filters and L-BAW based bulk AO filters have been demonstrated. As for integrated SAW based
0 filter, a 3-dB optical bandwidth of 2.5 nm, center wavelength of 1456 nm, and -20 dB distance of 14.49 nm are obtained at the SAW resonance
frequency of 189.94 MHz. Such filter requires 1 W RF power to achieve nearly complete polarization conversion. As for the bulk AO filter. a center Wavelength of 1472.5 nm is measured at the L-BAW resonance frequency of 328 MHz. In the bulk AO filter. full conversion cannot be reached even at
RF power up to 2 W. Comparing to the integrated (waveguide) filter. the efficiency of the bulk filter is significantly lower. The AO filter's central wavelength can be tuned by changing the RF power.
We investigated several designs to improve the AO filter efficiency. By optimizing the ASL transducer (coplanar electrodes with electrode width of 70 urn and gap of 20 t m), nearly complete optical switching at very low electrical powers (50mW) has been obtained, this corresponding to an
improvement factor of 20 compared to previous results. An appropriate mass-loading, placed on the surface and in between the electrodes of a
coplanar LiNb03 ASL, has allowed achieving strong lateral confinement of the acoustic field, thus leading to a significant improvement of the AO filter performance
Pemodelan Karakter Animasi Wayang Orang Berbasis Motion Capture
-- Desain karakter animasi memiliki keunikan dan menjadi daya tarik tersendiri bagi penggemar film animasi, berbagai macam bentuk karakter animasi telah ada sejak berdirinya industri film animasi, keragaman bentuk karakter animasi menimbulkan permasalahan, salah satunya adalah permasalahan retargeting file biovision yang diterapkan pada model karakter animasi, terutama pada karakter animasi stylized, bentuk dan ukuran anggota badan karakter stylized yang tidak proporsional menjadi permasalahan yang harus diantisipasi dalam tahapan perancangan karakter animasi motion capture, oleh karena itu diperlukan referensi yang terukur untuk membuat sistem riging karakter.Penelitian ini memetakan pemodelan karakter animasi menyerupai manusia stylized dengan tema pewayangan dalam kisah pewayangan di pulau Jawa dengan sistem auto-riging pada perangkat lunak open source yang dimodifikasi skala dan tranformasi tulangnya secara terukur supaya sesuai dengan proporsi gerakan file biovision dan menghasilkan animasi yang baik. Karakter animasi wayang orang yang digunakan dalam penelitian ini adalah karakter manusia yang dirancang secara tidak proporsional bentuk dan ukuran anggota badannya dengan tetap mempertahankan karakteristik utama bentuk manusia. Hasil pemodelan karakter animasi wayang stylized berbasis motion capture diharapkan menambah referensi bagi animator dalam bekerja lebih efektif dan efisien.
Preliminary Design Pada Perancangan Merchandise Resmi Untuk Revenue Generated ITS Sebagai PTNBH
The Revenue Generated ITS program as part of ITS Strategic Plan of PTNBH 2015-2019 provides a new challenge for ITS to develop business programs that departs from the intellectual result of all academic community. One of the opportunities that can be initiated is the development of official ITS merchandise products as a commercial product of ITS. ITS Merchandise product development efforts has been finding a variety of obstacles, ranging from inconsistencies between the products with each other, the quality of the existing product quality, up to the quality of the resulting product ideas. ITS Merchandise product development efforts are considered very urgent to be done immediately to see the high demand for ITS official merchandise products for various ITS activities. The method used in this research is the method of designing product design variants. Some stages of research include: (1) identification of design typology merchandise; (2) identification of consumers and product needs of ITS Merchandise; (3) Mapping merchandise product categories; (4) Development of product design merchandise variant; (5) Materials analysis and merchandise ITS Design Form; (6) Sampling of 1 prototype product; (7) Preparation of ITS Merchandise Product Design Guidelines. The approach used in variant product development in this research is ‘morphological chart’. The results to be achieved in this research is the identification of ITS Merchandise product line and its implementation, and A guide to merchandise product design development at production stage
Kompilasi Buku Cerita Anak sebagai Media Edukasi di Masa Pandemi
Abstrak—Pada masa pandemi ini, Satgas Covid-19 Institut Teknologi Sepuluh Nopember (ITS) bekerja sama dengan berbagai pihak terus berupaya memberikan informasi kepada masyarakat dalam rangka sosialisasi dan edukasi terkait penanganan pandemi. Salah satu luaran media yang digunakan oleh Satgas Covid-19 ITS bekerja sama dengan civitas akademika ITS untuk menyasar keluarga dan anak-anak adalah adalah buku cerita anak bergambar. Media tersebut dianggap memiliki kelebihan yang mencakup beberapa kriteria komunikasi, sehingga informasi di dalamnya dapat tersampaikan dengan baik melalui pesan berupa narasi dan visual. Diharapkan dengan buku kompilasi cerita anak tersebut, pesan edukasi dapat diserap melalui media yang lebih menarik, interaktif, dan mudah di akses oleh semua lapisan masyarakat.Abstract—During the Covid-19 pandemic. The task force of Institut Teknologi Sepuluh Nopember (ITS), in collaboration with various parties, continued to provide information to the public in the context of socializing and educating the handling of the pandemic. One of the external media used by the ITS Covid-19 task force in collaboration with the ITS academic community to target families and children is illustrated children's storybooks. The media is considered to have advantages that include several communication criteria so that the information in it can be conveyed properly through messages in the form of narration and visuals. It is hoped that with the compilation of children's stories, educational messages can be absorbed through media that are more interesting, interactive, and easily accessible to all levels of society
Quasi One-Dimensional Photonic Crystals as Building Block for Compact Integrated Optical Refractometric Sensors
A quasi one-dimensional photonic crystal has been fabricated and the applicability of this strong grating for optical sensing has been investigated by measuring the transmission spectra as a function of the cladding refractive index. The cladding index was varied a small range. By monitoring the transmitted output power the transmission stop-band was found to shift by 1 nm wavelength for either a cladding refractive index change of 0.05 or a temperature change of 120 K
Quasi 1-dimensional photonic crystals as building block for compact integrated optical sensors
A quasi one-dimensional photonic crystal has been fabricated and the applicability of this kind of structure for optical sensing has been investigated by measuring the transmission spectra as a function of the cladding refractive index. The cladding index was varied using a liquid flow, of which the index was slowly varied over a small range. The shift with cladding index of the steep stop band edge provides a relatively sensitive detection mechanism in an extremely compact device
0.3pA dark current and 0.65A/W responsivity 1020nm InGaAs/GaAs nano-ridge waveguide photodetector monolithically integrated on a 300-mm Si wafer
We report p-i-n InGaAs/GaAs multi-quantum well nano-ridge waveguide photodetectors monolithically integrated on a 300-mm Si wafer. The devices exhibit low dark currents of 0.3 pA ( 1.36Ă—10 -7 A/cm 2 ) at -1 V bias and internal responsivities of 0.65A/W at 1020nm wavelength
Ultraviolet laser-induced poling inhibition produces bulk domains in MgO-doped lithium niobate crystals
GaAs nano-ridge laser diodes fully fabricated in a 300 mm CMOS pilot line
Silicon photonics is a rapidly developing technology that promises to
revolutionize the way we communicate, compute, and sense the world. However,
the lack of highly scalable, native CMOS-integrated light sources is one of the
main factors hampering its widespread adoption. Despite significant progress in
hybrid and heterogeneous integration of III-V light sources on silicon,
monolithic integration by direct epitaxial growth of III-V materials remains
the pinnacle in realizing cost-effective on-chip light sources. Here, we report
the first electrically driven GaAs-based multi-quantum-well laser diodes fully
fabricated on 300 mm Si wafers in a CMOS pilot manufacturing line. GaAs
nano-ridge waveguides with embedded p-i-n diodes, InGaAs quantum wells and
InGaP passivation layers are grown with high quality at wafer scale, leveraging
selective-area epitaxy with aspect-ratio trapping. After III-V facet patterning
and standard CMOS contact metallization, room-temperature continuous-wave
lasing is demonstrated at wavelengths around 1020 nm in more than three hundred
devices across a wafer, with threshold currents as low as 5 mA, output powers
beyond 1 mW, laser linewidths down to 46 MHz, and laser operation up to 55
{\deg}C. These results illustrate the potential of the III-V/Si nano-ridge
engineering concept for the monolithic integration of laser diodes in a Si
photonics platform, enabling future cost-sensitive high-volume applications in
optical sensing, interconnects and beyond.Comment: 40 pages with 16 figures. pdf includes supplementary informatio