| 1-1 | Title | Growth of AlN Single Crystals and Applications for Future Electronics |
|---|---|---|
| Author(s) | Albrecht Winnacker, Professor | |
| Abstract | AlN is a very promising wide gap semiconductor material, but so far it cannot be provided as bulk material. In the talk the specific problems (high temperatures, material compatibility) in bulk growth of AlN will be presented together with the status of research on this problem. The potential for applications includes substrate material for blue and ultraviolet light emitting diodes (LEDs) and lasers, high frequency electronics and possibly electroacoustic devices due to the favorable piezoelectric properties, including very high velocity of surface acoustic waves. |
| 1-2 | Title | Optical Networking in the 21st Century: Challenges and Opportunities |
|---|---|---|
| Author(s) | Leonid Kazovsky, Professor | |
| Abstract | In the late 20th century, the main challenge in networking and communications was the inter- and cross-continental links. Long-haul optical networks and technologies were developed to successfully address that challenge. In the 21st century, access and, to a lesser extent, metro networks emerge as the main challenge in terms of both technologies and costs. The key technologies needed to address that new challenge include (1) passive optical networks evolving from TDM to WDM; (2) optical and wireless convergence; (3) efficient and transparent connectivity across home, access, and backbone networks; and (4) burst-mode transmission underlying the aforementioned technologies. |
| 1-3 | Title | Shaping the future: From nanostructures to nanotechnology |
|---|---|---|
| Author(s) | David Tománek, Professor | |
| Abstract | Gradual reduction of device dimensions to near-atomic size raises particular challenges in terms of component interconnection and fault tolerance. Due to fundamental limitations imposed on observations by the quantum behavior of these systems, predictive computer simulations emerge as a powerful approach to design complex nanostructures and to understand their behavior. I will illustrate how this approach allows to design new types of quantum conductors, including self-assembling Mo_12S_9I_9 nanowires, and optimize the contacts between nanotubes and leads for maximum transmission. The observed ability of nanostructures for selective self-healing of defects appears particularly important for mass production. |
| 5-1 | Title | Spin transport and spin transfer in modulated structures of (Ga,Mn)As |
|---|---|---|
| Author(s) | Tomasz Dietl, Professor | |
| Abstract | Recently developed theory for layered structures of carrier-controlled DMS, which combines the empirical tight-binding scheme with the Landauer-Btiker formalism will be presented. This approach describes properly the interfaces and inversion symmetry breaking as well as the band dispersion in the entire Brillouin zone. The application of this theory for quantitative description of experimental results, as obtained for (Ga,Mn)As-based device structures by Hideo Ohno and co-workers, will then be discussed, focusing on the magnitude and bias dependence of TMR, TAMR, and spin current polarization in Zener diodes as well as on domain-wall velocity and resistance. |
| 5-2 | Title | Spins, bytes and cures: science and technology of magnetic nanoparticles |
|---|---|---|
| Author(s) | Kannan Krishnan, Professor | |
| Abstract | Size-dependent scaling laws and the functional behavior of small particles and nanostructured assemblies, as a function of size, shape, dimensionality, morphology and inter-particle interactions, are increasingly of fundamental, technological and biomedical interest. Following a general introduction to these emerging areas of nanotechnology with emphasis on critical lengths scales, I will discuss a) Synthesis of monodispersed metallic/oxide nanoparticles with good control of their size, distribution, shapes and morphologies. b) How to tune the weak forces involved in their self-assembly to achieve square packing, hexagonal close packing, linear chains, spatially segregated arrays and liquid-crystal-like arrays with orientation order. c) Future applications including super high density data storage and the generation of a multifunction platform for diagnostics and therapy in biomedicine. |
| 5-3 | Title | Current Induced Magnetization Switching Study in MgO-based Magnetic Tunnel Junctions |
|---|---|---|
| Author(s) | Te-Ho Wu, Professor | |
| Abstract | Current induced magnetization switching (CIMS) discovered in 1996 by Slonczewski and Berger has been extensively studied in recent years, especially in magnetic random access memory (MRAM). CIMS is reversing the magnetization of a magnetic free layer in a multilayered structure with a current perpendicular to the plane. Moreover, it can simplify the process of read/write and increase density in MRAM application. In this study, the MgO-based MTJs structures are investigated. The samples were deposited by a sputtering system and patterned by ion milling lithography. CIMS was measured at room temperature using a DC four-point probe method after applying short current pulses with durations from 50 Ęsec to 10 msec. |
| 5-4 | Title | Beyond Magnetic Areal Density Growth: Systems' aspects of the Future Evolution of the Hard Disk Drive |
|---|---|---|
| Author(s) | Giora Tarnopolsky, President | |
| Abstract | The data permanency, random access, volumetric density, and re-writability of the magnetic hard disk drive (HDD) make it irreplaceable within the global electronic network. Increases of magnetic areal density seem assured by advances in media and head materials' systems. However, in order to meet global network system needs, the HDD needs to be improved: the physical longevity of the drive must increase rapidly with drive capacity, means to ensure data integrity over many decades should be developed, the data transfer frequency should increase proportionally to areal density, and the access time should decrease while maintaining reliability and a mass-produced mechanism. |
| 6-1 | Title | Radiation from Slotted Conducting Circular Cylinders |
|---|---|---|
| Author(s) | Hyo Yoon Eom, Professor | |
| Abstract | This paper summarizes the analysis for boundary-value problems of electromagnetic wave radiation from slotted conducting circular cylinders. Multiple circumferential and axial slots are considered in the analysis. Discrete and continuous eigenfunction expansions are utilized to express scattered fields. The techniques of Fourier transform and mode-matching are applied to match boundary conditions and to obtain a set of simultaneous equations. Convergent series solutions are obtained by using residue calculus. Computations are performed to investigate wave radiation characteristics. Slotted antennas were fabricated and their radiation patterns were measured at microwave frequencies. The measured data are in agreement with the theory. |
| 6-2 | Title | OFCDM - A Promising Wireless Broadband Access Technique |
|---|---|---|
| Author(s) | Jiangzhou Wang, Professor | |
| Abstract | Future mobile communication systems aim to provide extremely high speed data transmission, especially in downlink. The broadband orthogonal frequency and code division multiplexing (OFCDM) system with two-dimensional spreading (time and frequency domain spreading) is becoming a very promising technique for high speed wireless communications due to its advantages over OFDM. This paper presents the basic structure and main functions of the OFCDM system. The novel detection method for the OFCDM, called hybrid multicode interference (MCI) cancellation and minimum mean square error (MMSE) detection, is described. It has been shown in this paper that the OFCDM is superior to OFDM. |
| 6-3 | Title | Keyword Spotting in Broadcast News---Research at Voice Interface Lab at KAIST |
|---|---|---|
| Author(s) | Yung-Hwan Oh, Professor | |
| Abstract | In this presentation we introduce several research topics related with the keyword spotting system in broadcast news. The system searches the keyword speech in online broadcast news and extracts the articles including the keyword(s). To obtain a stable recognition performance, the system uses several speech processing techniques such as the confidence measure, out-of-vocabulary rejection, speech or speaker segmentation and noise reduction. We will show an overall configuration of our system and report technical advances as well as some experimental results. We also describe future works for the system improvements and for more complicated spoken interviews or movies. |
| 6-4 | Title | Ultrafast Photonic Signal Processing via Optical Fourier Domain Manipulation |
|---|---|---|
| Author(s) | Andrew Weiner, Professor | |
| Abstract | Ultrafast optical signal processing offers exciting possibilities to go beyond the processing speeds of electronics technologies for applications in high-speed fiber communications and ultrawideband wireless. In this talk I will review our recent work on processing of ultrafast optical signals via conversion between time, space, and optical frequency (Fourier) domains. Some specific topics that will be covered include optical arbitrary waveform generation, application of optical pulse shaping technologies for wavelength-parallel compensation of fiber transmission impairments, and new results on application of photonic methods for precompensation of dispersion effects in wireless transmission of radio-frequency signals over ultrawideband antenna links. |
| 22-1 | Title | Self-Organized Titanium Oxide Nanotube-Layers: Formation, Properties and Applications |
|---|---|---|
| Author(s) | Patrik Shmuki, Professor | |
| Abstract | The presentation demonstrates approaches to achieve electrochemical fabrication of self-organized high aspect ratio titanium oxide nanotube layers. Key to obtain highly defined tubes is an optimized and controlled anodization of titanium in fluoride containing solutions. In general, the morphology of the tubular layers is affected strongly by the electrochemical parameters such as solution pH and anodization voltage. By optimizing the local electrochemical conditions within the tubes, layers consisting of highly ordered TiO2 nanotubes with a length of several 10 micrometers can be grown on Ti surfaces. The diameters that can be obtained range from 20 nm to 200 nm with typical wall thicknesses in the range of 10-20 nm. Titanium oxide is a highly functional material that has, for example, interesting semiconductive or surface catalytic properties and therefore a high potential for technological exploitation. The talk will address a number of (potential) applications of the TiO2 nanotube layers in solar energy conversion, catalysis of decomposition of organic compounds (self-cleaning), wettability and biocompatibility. |
| 22-2 | Title | High Frequency Figures of Merit of Conventional and Schottky Barrier MOSFETs |
|---|---|---|
| Author(s) | François Danneville, Professor | |
| Abstract | This paper presents a review related to the high frequency (HF) figures of merit (FoM) of advanced MOSFETs, i.e. the current gain cut-off frequency ft, the maximum frequency of oscillation fmax and the minimum noise figure Fmin. In a first part, the state-of-the-art for each FoM is commented and limitations coming from the intrinsic part (short channel effects) or extrinsic part (access resistances, overlap/fringing capacitances) of the device are pointed out. In a second part, the HF performances of an alternative low schottky barrier source/drain contacts architecture, useful to overcome the technological breakthrough faced by conventional MOSFETs for up-coming nodes, are investigated. |
| 22-3 | Title | Design of efficient IIR digital filters based on sensitivity minimizations |
|---|---|---|
| Author(s) | Georgi Stoyanov, Professor | |
| Abstract | It is shown in this lecture how the inclusion of sensitivity minimization as a step of the design procedure can considerably improve the filter's efficiency. First, a strategy for sensitivity minimization of narrow-band filters is proposed. Then the best known methods to realize difficult specifications (with very high stop-band attenuation), based on parallel-all-pass-structure, tapped cascaded interconnection of identical all pass sub-filters and elliptical realization with minimal quality factors are investigated. It is shown that a minimization of the sensitivity over specific frequency ranges permits usage of a very short coefficient word-length, i.e. lower power consumption and computational burden, higher accuracy and simple multiplierless implementation. Similar results are obtained for variable and complex digital filters and for fractional delay filter realizations. The proposed methods are verified experimentally. |
| 22-4 | Title | Quantum optics treatment of surface-enhanced Raman scattering |
|---|---|---|
| Author(s) | Peter Johansson, Professor | |
| Abstract | We present a general model study of surface-enhanced resonant Raman scattering and fluorescence focusing on the interplay between electromagnetic effects and the molecular dynamics. Our model molecule is placed close to two Ag nanoparticles, and has two electronic levels. A Franck-Condon mechanism provides electron-vibration coupling. Using realistic parameter values for the molecule we find that an electromagnetic enhancement by 10 orders of magnitude can yield Raman cross-sections of the order 10-14cm2. |