Tailoring electronic properties of multilayer phosphorene by siliconization

Controlling a thickness dependence of electronic properties for two-dimensional (2d) materials is among primary goals for their large-scale applications. Herein, employing a first-principles computational approach, we predict that Si interaction with multilayer phosphorene (2d-P) can result in the formation of highly stable 2d-SiP and 2d-SiP$_2$ compounds with a weak interlayer interaction. Our analysis demonstrates that these systems are semiconductors with band gap energies that can be governed by varying the thickness and stacking order. Specifically, siliconization of phosphorene allows to design 2d-SiP$_x$ materials with significantly weaker thickness dependence of electronic properties than that in 2d-P and to develop ways for their tailoring. We also reveal the spatial dependence of electronic properties for 2d-SiP$_x$ highlighting difference in effective band gaps for different layers. Particularly, our results show that central layers in the multilayer 2d systems determine overall electronic properties, while the role of the outermost layers is noticeably smaller

Delivering Bio-Mems & Microfluidic Education Around Accessible Technologies

Electronic Systems are now being deployed in al-most all aspects of daily life as opposed to being confined to consumer electronics, computing, communication and control applications as was the case in the 90’s. One of the more significant growth areas is medical instrumentation, health care, bio-chemical analysis and environmental monitoring. Most of these applications will in the future require the integration of fluidics and biology within complex electronic systems. We are now seeing technologies emerging together with access services such as the FP6 “INTEGRAMplus” and “MicroBuilder” programs that offer competitive solutions for companies wishing to de-sign and prototype microfluidic systems. For successful deployment of these systems, a new breed of electronic engineers are needed that understand how to deliver bio-chemistry and living cells to transducers and integrate the required technologies reliably into robust systems. This paper will report on initial training initiatives now active under the INTEGRAMplus program

Electrically packaged silicon-organic hybrid (SOH) I/Q-modulator for 64 GBd operation

Silicon-organic hybrid (SOH) electro-optic (EO) modulators combine small footprint with low operating voltage and hence low power dissipation, thus lending themselves to on-chip integration of large-scale device arrays. Here we demonstrate an electrical packaging concept that enables high-density radio-frequency (RF) interfaces between on-chip SOH devices and external circuits. The concept combines high-resolution $\mathrm{Al_2O_3}$ printed-circuit boards with technically simple metal wire bonds and is amenable to packaging of device arrays with small on-chip bond pad pitches. In a set of experiments, we characterize the performance of the underlying RF building blocks and we demonstrate the viability of the overall concept by generation of high-speed optical communication signals. Achieving line rates (symbols rates) of 128 Gbit/s (64 GBd) using quadrature-phase-shiftkeying (QPSK) modulation and of 160 Gbit/s (40 GBd) using 16-state quadrature-amplitudemodulation (16QAM), we believe that our demonstration represents an important step in bringing SOH modulators from proof-of-concept experiments to deployment in commercial environments

A Study of the Relationship Between Antivirus Regressions and Label Changes

AntiVirus (AV) products use multiple components to detect malware. A component which is found in virtually all AVs is the signature-based detection engine: this component assigns a particular signature label to a malware that the AV detects. In previous analysis [1-3], we observed cases of regressions in several different AVs: i.e. cases where on a particular date a given AV detects a given malware but on a later date the same AV fails to detect the same malware. We studied this aspect further by analyzing the only externally observable behaviors from these AVs, namely whether AV engines detect a malware and what labels they assign to the detected malware. In this paper we present the results of the analysis about the relationship between the changing of the labels with which AV vendors recognize malware and the AV regressions

Recent Advances in High-k Nanocomposite Materials for Embedded Capacitor Applications

©2008 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or distribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.DOI: 10.1109/TDEI.2008.4656240In this paper, a wide variety of high dielectric constant (k) composite materials which have been developed and evaluated for embedded capacitor application are reviewed. Current research efforts toward achieving high dielectric performance including highk and low dielectric loss for polymer composites are presented. New insights into the effect of unique properties of the nanoparticle filler, filler modification and the dispersion between filler and polymer matrix on the dielectric properties of the nanocomposites are discussed in details

Spontaneous breaking of time reversal symmetry in strongly interacting two dimensional electron layers in silicon and germanium

We report experimental evidence of a remarkable spontaneous time reversal symmetry breaking in two dimensional electron systems formed by atomically confined doping of phosphorus (P) atoms inside bulk crystalline silicon (Si) and germanium (Ge). Weak localization corrections to the conductivity and the universal conductance fluctuations were both found to decrease rapidly with decreasing doping in the Si:P and Ge:P $\delta-$layers, suggesting an effect driven by Coulomb interactions. In-plane magnetotransport measurements indicate the presence of intrinsic local spin fluctuations at low doping, providing a microscopic mechanism for spontaneous lifting of the time reversal symmetry. Our experiments suggest the emergence of a new many-body quantum state when two dimensional electrons are confined to narrow half-filled impurity bands

Optical Supersymmetry in the Time Domain

Originally emerged within the context of string and quantum field theory, and later fruitfully extrapolated to photonics, the algebraic transformations of quantum-mechanical supersymmetry were conceived in the space realm. Here, we introduce a paradigm shift, demonstrating that Maxwell's equations also possess an underlying supersymmetry in the time domain. As a result, we obtain a simple analytic relation between the scattering coefficients of a large variety of time-varying optical systems and uncover a wide new class of reflectionless, three dimensional, all-dielectric, isotropic, omnidirectional, polarization-independent, non-complex media. Temporal supersymmetry is also shown to arise in dispersive media supporting temporal bound states, which allows engineering their momentum spectra and dispersive properties. These unprecedented features define a promising design platform for free-space and integrated photonics, enabling the creation of a number of novel reconfigurable reflectionless devices, such as frequency-selective, polarization-independent and omnidirectional invisible materials, compact frequency-independent phase shifters, broadband isolators, and versatile pulse-shape transformers