Field Of Information Processing Research Articles

Ultra-wide band dispersionless slow light waveguides

In conventional slow light waveguide, the delay time of signal in a waveguide is inversely proportional to its bandwidth. As a measure of storage density of optical pulse, the delay-bandwidth product is limited to a small constant depending on waveguiding approach. Breaking the limit is fundamental problem in optical signal and quantum information processing fields. The solution to this problem is becoming increasingly important, especially with high-speed signal processing system. So far, there have been neither practical nor realizable techniques that can solve this problem. In this paper, we propose a mechanism to explore the possibility for breaking the delay-bandwidth limit by using ultra-flat photonic band cluster. We show that based on multiple micro-cavities having corresponding multiple ultra-flat photonic bands, a slow light with arbitrary bandwidth in frequency can be achieved with ultraslow group velocity and ultralow group velocity dispersion, leading to a broken delay-bandwidth limit. This work demonstrates that arbitrary bandwidth dispersionless slow light can be realized with a two-dimensional multiple-microcavity photonic-crystal line-defect waveguide.

A Compact Optical Switch via Plasmonics of Subwavelength Circular‐Sharp Hole Arrays in Metal Films

AbstractWe studied numerically the enhanced optical transmission (EOT) through periodic subwavelength circular‐sharp hole arrays in metallic films with different edge sharp distribution features of unit structures. Detailed studies indicate that the unit structure edge sharp distribution features strongly influence the surface plasmons (SPs). These results demonstrate that the number of edge sharp activated the localized surface plamons (LSP) resonance on the unit structure is changed by rotating the polarization of the incident light, leading to change the infrared transmittance of the array. Moreover, a compact plasmonic switch via periodic circular‐sharp hole arrays based on the dependence of SPs on unit structural edge sharp distributions is proposed. The finding provides a new idea for designing plasmonics devices, and expands the application range of metal micro‐nano structure in the field of optical communications and information processing.

Continuous-variable entanglement of two bright coherent states that never interacted

We study continuous-variable entanglement of bright quantum states in a pair of evanescently coupled nonlinear $\chi^{(2)}$ waveguides operating in the regime of degenerate down-conversion. We consider the case where only the energy of the nonlinearly generated fields is exchanged between the waveguides while the pump fields stay independently guided in each original waveguide. We show that this device, when operated in the depletion regime, entangles the two non-interacting bright pump modes due to a nonlinear cascade effect. It is also shown that two-colour quadripartite entanglement can be produced when certain system parameters are appropriately set. This device works in the traveling-wave configuration, such that the generated quantum light shows a broad spectrum. The proposed device can be easily realized with current technology and therefore stands as a good candidate for a source of bipartite or multipartite entangled states for the emerging field of optical continuous-variable quantum information processing.

Experimental demonstration of an optical Feynman gate for reversible logic operation using silicon micro-ring resonators

Abstract Currently, the reversible logic circuit is a popular research topic in the field of information processing as it is a most effective approach to minimize power consumption, which can achieve the one-to-one mapping function to identify the input signals from its corresponding output signals. In this letter, we propose and experimentally demonstrate an optical Feynman gate for reversible logic operation using silicon micro-ring resonators (MRRs). Two electrical input signals (logic operands) are applied across the micro-heaters above MRRs to determine the switching states of MRRs, and the reversible logic operation results are directed to the output ports in the form of light, respectively. For proof of concept, the thermo-optic modulation scheme is used to achieve MRR’s optical switching function. At last, a Feynman gate for reversible logic operation with the speed of 10 kbps is demonstrated successfully.

An adaptive algorithm for single-trial P300 evoked potential extraction based on dynamic feature library

Objective The single-trial extraction method of evoked potential has been one of the problems in EEG information processing field. According to the characteristics of somatosensory evoked electroencephalogram (EEG) with low signal-to-noise ratio and large parameter variation between trials, a novel single-trial extraction method for evoked potentials was proposed. This method aims to further improve the accuracy and characteristics of the single-trial extraction algorithm, preserve more dynamic characteristics between trials, and improve the estimation accuracy. Methods Based on wavelet filtering and multiple linear analysis, a new single-trial extraction method for EEG P300 parameters was proposed by applying the adaptive dynamic feature library. Four groups of wavelet filtered evoked EEG data were randomly selected, and used to build the feature library using overlapping average method and principal component analysis. For the single-trial extracted EEG data, the component with the highest correlation coefficient related with the current data was selected as the independent variable from the feature library, and the relevant multiple linear regression analysis was conducted. The single-trial evoked potential signal was reconstructed by the regression analysis results, in which the key features such as latency and amplitude were automatically extracted. Results Compared with the benchmark values determined by experts, the proposed algorithm can obtain more accurate estimation values of latency and amplitude in P300 components. The average difference of latency and amplitude by the proposed algorithm is (11.16±8.60) ms and (1.40±1.34) μV, respectively. These two values obtained by the proposed algorithm are much closer to that obtained by the commonly used overlapping average method of (23.26 ± 25.76) ms and (2.52 ± 2.50) μV, respectively. These results show that the proposed algorithm has significant advantages comparing with the traditional multiple linear regression analysis algorithm. Conclusions The dynamic updating principal component sample library of EEG data was applied to wavelet filtering and multiple linear regression, thus the dynamic characteristics were effectively preserved, and the accuracy of parameter estimation was improved. Key words: Multiple linear regression with dispersion terms; Evoked electroencephalogram; P300; Principal component analysis

S141 Aging and automatic detection of deviancy in vision: Event-related potential studies

Objectives We investigated the possibility of age-related differences in automatic visual change detection. It is well-established that efficiency of various kinds of attentional processes decreases in elderly, but our knowledge on the field of automatic information processing is limited. Methods Visual mismatch negativity (vMNN) component of event-related brain activity was investigated in three experiments. Using checkerboard stimuli we developed a method capable of quick assessment of vMMN. In a new paradigm with offset responses we controlled low-level adaptation processes, and in the third experiment we investigated the possibility of age-related change in visual persistence. Results Early phase of vMMN was preserved in the older group. However, in a later range of vMMN we obtained decreased amplitude in elderly. In the older group vMMN indicated a longer perceptual persistence. Discussion Automatic detection of environmental change is preserved in older age, but evaluation of the changing stimulation become less efficient. The increased persistence is a sign of compromised temporal acuity in the older sample. Conclusion Like in the field of attentive visual processing, we obtained event-related brain electric activity changes in the domain of automatic perceptual processing. Significance VMMN seems to be a proper method for assessing compromised visual processing in “healthy” aging, and the results open a possibility for investigating various pathological conditions frequently present in aged populations.

Quantum red–green–blue image steganography

One of the most considering matters in the field of quantum information processing is quantum data hiding including quantum steganography and quantum watermarking. This field is an efficient tool for protecting any kind of digital data. In this paper, three quantum color images steganography algorithms are investigated based on Least Significant Bit (LSB). The first algorithm employs only one of the image’s channels to cover secret data. The second procedure is based on LSB XORing technique, and the last algorithm utilizes two channels to cover the color image for hiding secret quantum data. The performances of the proposed schemes are analyzed by using software simulations in MATLAB environment. The analysis of PSNR, BER and Histogram graphs indicate that the presented schemes exhibit acceptable performances and also theoretical analysis demonstrates that the networks complexity of the approaches scales squarely.

Research on Tibetan hot words, sensitive words tracking and public opinion classification

The rapid development of Tibetan information technology provides rich resources for Tibetan information processing technology. The construction of Tibetan corpus is the field of Tibetan information processing of basic work. In this paper, we design the system of Tibetan network data collection and web pages preprocessing. It can timely and efficiently access to web resources, and provide a basis for further analysis of Tibetan data. It can establish the Tibetan related corpus, enrich the Tibetan digital resources. It can also alleviate the status of Tibetan corpus data sparse and lack of resources and bring the convenient condition for Tibetan information processing. The hot words reflect the hot spot of Tibetan people’s attention in a certain period of time. Firstly, the paper proposes the method for reducing the space dimension of Tibetan news text. It can effectively reduce the complexity of subsequent processing. Secondly, term weighting method is proposed based on improved TFIDF for Tibetan text information extraction. It utilizes the idea that the words of different locations are given different weights to extract the hot words. On sensitive words discovery and classification of public opinion, sensitive thesaurus are collected artificially. Through the sensitive thesaurus comparison, the sensitive words are extracted. Classification of public opinion words is based on the proposed classification formula and the public opinion thesaurus. It will classify one Tibetan text to one public opinion class. In this paper, the software is developed to automatically collect Tibetan web pages from the network, preprocess the web pages, extract the text features and hot words, discover the sensitive words and classify the Tibetan text to one public opinion class. The experiment shows that the Tibetan hot words extraction is effective and Tibetan classification results of public opinion are significant.

Arbitrarily exhaustive hypergraph generation of 4-, 6-, 8-, 16-, and 32-dimensional quantum contextual sets

Quantum contextuality turns out to be a necessary resource for universal quantum computation and important in the field of quantum information processing. It is therefore of interest both for theoretical considerations and for experimental implementation to find new types and instances of contextual sets and develop methods of their optimal generation. We present an arbitrary exhaustive hypergraph-based generation of the most explored contextual sets---Kochen-Specker (KS) ones---in 4, 6, 8, 16, and 32 dimensions. We consider and analyse twelve KS classes and obtain numerous properties of theirs, which we then compare with the results previously obtained in the literature. We generate several thousand times more types and instances of KS sets than previously known. All KS sets in three of the classes and in the upper part of a fourth are novel. We make use of the MMP hypergraph language, algorithms, and programs to generate KS sets strictly following their definition from the Kochen-Specker theorem. This approach proves to be particularly advantageous over the parity-proof-based ones (which prevail in the literature), since it turns out that only a very few KS sets have a parity proof (in six KS classes 0.01% and in one of them 0%). MMP hypergraph formalism enables a translation of an exponentially complex task of solving systems of nonlinearequations, describing KS vector orthogonalities, into a statistically linearly complex task of evaluating vertex states of hypergraph edges, thus exponentially speeding up the generation of KS sets and enabling us to generate billions of novel instances of them. The MMP hypergraph notation also enables us to graphically represent KS sets and to visually discern their features.

Von Neumann entropy in a Rashba-Dresselhaus nanodot; dynamical electronic spin-orbit entanglement

The main purpose of the present article is to report the characteristics of von Neumann entropy, thereby, the electronic hybrid entanglement, in the heterojunction of two semiconductors, with due attention to the Rashba and Dresselhaus spin-orbit interactions. To this end, we cast the von Neumann entropy in terms of spin polarization and compute its time evolution; with a vast span of applications. It is assumed that gate potentials are applied to the heterojunction, providing a two dimensional parabolic confining potential (forming an isotropic nanodot at the junction), as well as means of controlling the spin-orbit couplings. The spin degeneracy is also removed, even at electronic zero momentum, by the presence of an external magnetic field which, in turn, leads to the appearance of Landau states. We then proceed by computing the time evolution of the corresponding von Neumann entropy from a separable (spin-polarized) initial state. The von Neumann entropy, as we show, indicates that electronic hybrid entanglement does occur between spin and two-dimensional Landau levels. Our results also show that von Neumann entropy, as well as the degree of spin-orbit entanglement, periodically collapses and revives. The characteristics of such behavior; period, amplitude, etc., are shown to be determined from the controllable external agents. Moreover, it is demonstrated that the phenomenon of collapse-revivals’ in the behavior of von Neumann entropy, equivalently, electronic hybrid entanglement, is accompanied by plateaus (of great importance in quantum computation schemes) whose durations are, again, controlled by the external elements. Along these lines, we also make a comparison between effects of the two spin-orbit couplings on the entanglement (von Neumann entropy) characteristics. The finer details of the electronic hybrid entanglement, which may be easily verified through spin polarization measurements, are also accreted and discussed. The novel results of the present article, with potent applications in the field of quantum information processing, provide a deeper understanding of the electronic von Neumann entropy and hybrid entanglement that occurs in two-dimensional nanodots.

A new fabrication method for nano-gratings based on the high flexibility of PDMS

A new method for simple and low-cost fabrication of nano-grating structures is reported in this paper. First, microscale grating structures on the master mold are replicated into Polydimethylsiloxane(PDMS), which serves as an intermediate, negative mold, by a conventional soft lithography process. The PDMS negative mold was then stretched along the direction of the grating lines to reduce the period of grating. Last, transfer the grating pattern from the PDMS membrane to PMMA. Nano-grating can be fabricated on polymethylmethacrylate(PMMA) by repeating the steps for several times. The grating has been tested and performs the width of 820nm. The technology, utilizing the high elasticity of PDMS and the nano-molding technology, can be used to fabricate nano-gratings in low-cost and no expensive or high precision equipment. Because of the excellent replication property of PDMS molds, a large number of gratings can be made with a single master mold. The nano-gratings can be widely used in the optical measurement, integrated optics, optical information processing and other fields.

Automating quantum experiment control

The field of quantum information processing is rapidly advancing. As the control of quantum systems approaches the level needed for useful computation, the physical hardware underlying the quantum systems is becoming increasingly complex. It is already becoming impractical to manually code control for the larger hardware implementations. In this chapter, we will employ an approach to the problem of system control that parallels compiler design for a classical computer. We will start with a candidate quantum computing technology, the surface electrode ion trap, and build a system instruction language which can be generated from a simple machine-independent programming language via compilation. We incorporate compile time generation of ion routing that separates the algorithm description from the physical geometry of the hardware. Extending this approach to automatic routing at run time allows for automated initialization of qubit number and placement and additionally allows for automated recovery after catastrophic events such as qubit loss. To show that these systems can handle real hardware, we present a simple demonstration system that routes two ions around a multi-zone ion trap and handles ion loss and ion placement. While we will mainly use examples from transport-based ion trap quantum computing, many of the issues and solutions are applicable to other architectures.

Special Article Series on Signal Processing Education via Hands-On and Design Projects [From the Guest Editors

As professionals in the signal and information processing field, we build on the tools and theories we learned in our undergraduate studies, adding knowledge and skills over the years. For many of us, it has been a while since our undergraduate studies, yet we can probably recall some of these “Ahha” moments when a full meaning of some fundamental theory sank in. As educators and mentors, we seize on these moments and our own experiences to implement new successful teaching methods that advance effective learning and skill development.

Recent progress of the application of surface plasmon polariton in quantum information processing

Surface plasmon polariton has attracted more and more attention and has been studied extensively in the recent decades, owing to its ability to confine the electro-magnetic field to a sub-wavelength scale near the metal-dielectric interface. On one hand, the tightly confined surface plasmonic modes can reduce the size of integrated optical device beyond the diffraction limit; on the other hand, it provides an approach to enhancing the interaction between light and matter. With the development of experimental and numerical simulation techniques, its investigation at a quantum level has become possible. In the recent experiments, scientists have realized quantum interference between single plasmons in a nanoscale waveguide circuit and achieved the strong coupling between photons and single molecules by using plasmonic structure, which demonstrates its superiority over the traditional optics. Here, we review the theoretical and experimental researches of surface plasmon polariton in the field of quantum information processing. First, we introduce the experiments on the basic quantum properties of surface plasmons, including the preservation of photonic entanglement, wave-particle duality and quantum statistical property. Second, we review the research work relating to the generation, manipulation and detection of surface plasmons in a quantum plasmonic integrated circuit. Then, we present the research of the interaction between surface plasmons and single quantum emitters and its potential applications. Finally, we make a discussion on how the intrinsic loss affects the quantum interference of single plasmons and the coupling between quantum emitters. The collision and combination of quantum optical and plasmonic fields open up possibilities for investigating the fundamental quantum physical properties of surface plasmons. It can be used to make ultra-compact quantum photonic integrated circuits and enhance the interaction strength between photons and quantum emitters.

Performance optimization of GNRFET Inverter at 32nm technology node

Moore’s law has been an important benchmark for developments in the field of microelectronics & information processing. In fact, it has played an instrumental role in driving the world economics and scaling down of the feature length has been the fundamental strategy for improving the performance of the device. However, as we continue to scale down, towards the nanometre regime, various factors like line edge roughness, tunnelling effects, random dopant fluctuations, short channel effects etc tends to effect it’s functioning and thereupon, it’s become of acute essence to investigate other alternative materials that could help extend the saturating Moore’s Law. A lot of research is currently going in the area and many alternative technologies like CNFETs, FINFETs, GNRFETs etc. are being explored. Field-effect transistors using Graphene Nano-Ribbons (GNRFETs) have emerged as promising technology because of their excellent carrier transport properties and potential for large scale processing and fabrication. This paper explores the GNRFETs inverter performance with CMOS inverter at 32nm technology node. Simulations indicate about 2.5x improvements in the propagation delay and 2x improvements in the power delay product (PDP). Further optimization of results was obtained by varying the number of Nano-Ribbons along with the supply voltage. On varying the number of nano-ribbons it was found that, propagation delay decreases, while dynamic energy consumption increases. Based on the inference, the optimized result was chosen to be 15 nano-ribbon. The results indicate that that GNRFET is a promising alternative for Si-CMOS, making it an excellent proposition to help extend the saturating Moore’s Law.

Temperature dependent characteristics of photo-induced birefringence in different types of azo materials

At different temperatures, a semiconductor laser with a wavelength of 650 nm is used as probe light, and an Nd:YAG continuous laser with a wavelength of 532 nm is selected as pump light. The azo samples are placed between a pair of orthogonal polarizers with the vertical direction clockwise and counterclockwise 45 degrees, respectively. The polarization direction of the pump light is set to be the vertical direction. In order to reduce the effect of the stray light, a chopper is placed in the optical path of the probe light. The signal of photo-induced birefringence is recorded by a phase-locked amplifier (NF-LI5640). The photo-induced birefringences of the doped azo material, the azo polymer and the azo liquid crystal polymer are measured respectively, and the dynamic processes of photo-induced birefringence are fitted by a double e-index model. The experimental results show that with the influence of the pump light, photo-induced birefringences of the three types of azo materials rise rapidly at first and then gradually tend to reach their own saturation state because of the photo-induced cis and trans isomerism and the photo-induced molecular orientation properties of azo molecules. The photo-induced birefringence shows a tendency to increase at first and then decrease with the temperature increasing, which can be understood as a competitive mechanism. The photo-induced birefringence depends on the photo-induced orientation and irregular thermal motions of azo groups. In the range below the glass transition temperature of the samples, the increase of the temperature of samples contributes to the rearrangement of the azo molecules due to the influence of the pump light. When the temperature of the samples is higher than the glass transition temperature, molecular chains begin to move. The irregular thermal motions of azo components and polymer molecules are aggravated. This destroys the orientations of the polymer molecules and results in the drop of the photo-induced birefringence. Comparing the doped azo material with the azo polymer sample, the azo liquid crystal polymer sample exhibits not only a larger photo-birefringence, but also the photo-induced birefringence that does not change obviously after the pump light has been turned off, which means that the azo liquid crystal polymer sample has long optical storage properties. This shows that the azo liquid crystal polymer material is an ideal polarization-sensitive optical recording medium, which is expected to be used in the fields of optical storage, polarization holography and optical information processing.

Practical Solutions to Foreign Language Training Courses Implemented Using Distance Learning Tools

The present study investigates the practical solutions to foreign language training courses implemented using distance learning tools. It reveals inefficiency of existing distance learning practice as its main features and tools remain virtually untapped, neither there is an opportunity to achieve the learning outcomes specified by curriculum planning documentation. To ensure an optimal design of this study course it is necessary to consider two interdependent factors: curriculum requirements for learning outcomes (competences developed) and specific features of distance learning tools contributing to the development of these competences. On this basis, the authors design a structure of a foreign language course, providing for the development of all kinds of speech activity, as well as academic skills in the field of information search, analysis and processing, as well as strategic skills in the field of independent research and professional activities. The proposed Learning design (Conceptual map) is in many ways incomplete but the authors suppose that practicing educators may use its separate components to assist with designing and implementing effective teaching and learn­ing activities, where the effectiveness is ultimately meas­ured in terms of learning outcomes rather than teaching inputs. For most educators, this means using a wide range of teaching and learning approaches depending on what is most effective in their context. And to the extent that sharing learning designs helps educators to adopt new, effective teaching and learning methods, then ultimately student learning will improve.

Many-bodyab initiostudy of antiferromagnetic{Cr7M}molecular rings

Antiferromagnetic molecular rings are widely studied both for fundamental quantum-mechanical issues and for technological applications, particularly in the field of quantum information processing. Here we present a detailed first-principles study of two families---purple and green---of ${{\mathrm{Cr}}_{7}M}$ antiferromagnetic rings, where $M$ is a divalent transition metal ion ($M={\mathrm{Ni}}^{2+}, {\mathrm{Mn}}^{2+}$, and ${\mathrm{Zn}}^{2+}$). We employ a recently developed flexible and efficient scheme to build ab initio system-specific Hubbard models. From such many-body models we systematically derive the low-energy effective spin Hamiltonian for the rings. Our approach allows us to calculate isotropic as well as anisotropic terms of the spin Hamiltonian, without any a priori assumption on its form. For each compound we calculate magnetic exchange couplings, zero-field splitting tensors, and gyromagnetic tensors, finding good agreement with experimental results.

Automatic Parameter Selection for Intensity-Based Registration of Imagery to LiDAR Data

Automatic registration of multisensor data, for example, imagery and Light Detection And Ranging (LiDAR), is a basic step in data fusion in the field of geospatial information processing. Mutual information (MI) has recently attracted research attention as a statistical similarity measure for intensity-based registration of multisensor images in the related fields of computer vision and remote sensing. Since MI-based registration methods rely on joint probability density functions (pdfs) for the data sets, errors in pdf estimation can affect the MI value, causing registration failure due to the presence of nonmonotonic surfaces of similarity measure. The quality of the estimated pdf is highly dependent upon both the bin size and the smoothing technique used in the pdf estimation procedure. The lack of a general approach to assign an appropriate bin size value for the pdf of multisensor data reduces both the level of automation and the robustness of the registration. In this paper, a novel bin size selection approach is proposed to improve registration reliability. The proposed method determines the best (uniform or variable) bin size for the pdf estimation via an analysis of the relationship between the similarity measure values of the data and the adopted geometric transformation. This highlights the role of the component of MI sensitive to the transformation, rather than the MI component that is unrelated to the transformation, such as noise. The performance of the proposed method for the registration of aerial imagery to LiDAR point clouds is investigated, and experimental results are compared with those achieved through a feature-based registration method.

Implementing All-Optical New Reversible Gate using SOA-MZI Architecture

Reversible circuits have gained a lot of attention lately because of its remarkable property of dissipating lesser power as compared to irreversible circuits due to the fact that they do not lose information. Because of continuing revolution in VLSI technology transistor count and thus power dissipation has increased to such an extent that it has put a limit on packing density and performance of the circuits. To overcome these limits reversible logic has came into picture and various reversible logic gates such as Feynman gate, Fredkin gate, Toffoli gate, Peres gate etc has already been designed in optical domain. Semiconductor optical amplifier (SOA) based mach-Zehnder interferometer (MZI) plays a promising role in this field of ultra fast all-optical information processing because of its advantages like high speed, low power, easy of fabrication and fast switching time. Thus various circuits designed by these basic gates has been analysed in terms of cost parameters and it was seen that optical cost and delay of digital circuits is more than desired, as a result performance of system is rendered. Thus new gates are designed by various researchers that focus on improving cost and thus performance of the system. Studying all these modified gates and the digital circuits implemented in literature, an idea of New All-optical universal reversible gate has been proposed which will further improve the performance of digital circuits. Applications of this gate include the design of full adder, half adder, multiplexer and various other combinational circuits and also 13 standard Boolean expressions can be implemented with improved cost. Simulation of this new gate is done using VPI Photonics software.