Nonlinear Integrated Photonics in the Visible Spectrum Based on III-N Material Platform

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Description
Photonic integrated circuit (PIC) in the visible spectrum opens up new opportunities for frequency metrology, neurophotonics, and quantum technologies. Group III nitride (III-N) compound semiconductor is a new emerging material platform for PIC in visible spectrum. The ultra-wide bandgap of

Photonic integrated circuit (PIC) in the visible spectrum opens up new opportunities for frequency metrology, neurophotonics, and quantum technologies. Group III nitride (III-N) compound semiconductor is a new emerging material platform for PIC in visible spectrum. The ultra-wide bandgap of aluminum nitride (AlN) allows broadband transparency. The high quantum efficiency of indium gallium nitride (InGaN) quantum well is the major enabler for solid-state lighting and provides the opportunities for active photonic integration. Additionally, the two-dimensional electron gas induced by spontaneous and polarization charges within III-N materials exhibit large electron mobility, which is promising for the development of high frequency transistors. Moreover, the noncentrosymmetric crystalline structure gives nonzero second order susceptibility, beneficial for the application of second harmonic generation and entangled photon generation in nonlinear and quantum optical technologies. Despite the promising features of III-N materials, the investigations on the III-N based PICs are still primitive, mainly due to the difficulties in material growth and the lack of knowledge on fundamental material parameters. In this work, firstly, the fundamental nonlinear optical properties of III-N materials will be characterized. Then, the fabrication process flow of III-N materials will be established. Thirdly, the waveguide performance will be theoretically and experimentally evaluated. At last, the supercontinuum generation from visible to infrared will be demonstrated by utilizing soliton dynamics in high order guided modes. The outcome from this work paves the way towards fully integrated optical comb in UV and visible spectrum.
Date Created
2020
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Analysis of the Impact of Strong Ties Between a Retail Company and its Customer – An Empirical Analysis and Case Study of Kid’s Want, a Maternal and Child Products Retail Company

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Description
Due to the booming young mothers and fathers in the new era as well as the changes in the concept of parenting and the favorable liberalization of China's second child policy, the maternal-baby nursing market continues to grow, and it

Due to the booming young mothers and fathers in the new era as well as the changes in the concept of parenting and the favorable liberalization of China's second child policy, the maternal-baby nursing market continues to grow, and it has become a must for businesses nowadays. In 2020, the size of the maternal-baby nursing market will reach 3.6 trillion. (Data: Yibang Power China's Maternal and Child Industry White Paper 2017).

The rapid development of mobile Internet, highly transparent information, consumers grasp the sovereignty, along with the rise of the middle class, consumption increase encouraged personalized, customized needs. The boundaries between online and offline are becoming increasingly blurred. Consumers are more inclined to choose multi-category with service channel providers. If the retailers still rely on good market resources, and the difference between the sales and purchase of commodities, they will face a huge challenge of the decrease in passenger flow and a decline in performance.

The paper takes the relationship between maternal-baby nursing retailers and targets customers as the study object, based on customer service of maternal-baby nursing retailer data, empirical studies, we found that this particular group, mothers and babies, especially value safety, quality, public praise and community review. If the retail enterprise attaches importance to establishing relationships with customers and enhances the relational viscosity through mutual trust, emotional formation and spread of public praise, it will help to increase the traffic volume and increase the output value of single customers.

The maternal-baby nursing retailers form a strong relationship between enterprises and customers by establishing a strong relationship between products and customers, employees and customers, and customers to customers. Maternal-baby nursing retailers operate single-customer value deeply, build a heavy membership system and manage customer assets, thereby enhancing their brand and performance.

The research on the method of establishing the strong tie can be considered as an analysis of feasibility. The research results of this paper will help to improve the overall customer service experience and satisfaction of the mother and infant retail industry, enhance the development of the whole industry and draw significance lessons from other service industries.
Date Created
2018
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Crystal Orientation Dependent Intersubband Transition in Semipolar AlGaN/GaN Single Quantum Well for Optoelectronic Applications

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Description

The optical properties of intersubband transition in a semipolar AlGaN/GaN single quantum well (SQW) are theoretically studied, and the results are compared with polar c-plane and nonpolar m-plane structures. The intersubband transition frequency, dipole matrix elements, and absorption spectra are

The optical properties of intersubband transition in a semipolar AlGaN/GaN single quantum well (SQW) are theoretically studied, and the results are compared with polar c-plane and nonpolar m-plane structures. The intersubband transition frequency, dipole matrix elements, and absorption spectra are calculated for SQW on different semipolar planes. It is found that SQW on a certain group of semipolar planes (55° < θ < 90° tilted from c-plane) exhibits low transition frequency and long wavelength response with high absorption quantum efficiency, which is attributed to the weak polarization-related effects. Furthermore, these semipolar SQWs show tunable transition frequency and absorption wavelength with different quantum well thicknesses, and stable device performance can be achieved with changing barrier thickness and Al compositions. All the results indicate that the semipolar AlGaN/GaN quantum wells are promising candidate for the design and fabrication of high performance low frequency and long wavelength optoelectronic devices.

Date Created
2016-05-05
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Analysis of Loss Mechanisms in InGaN Solar Cells Using a Semi-Analytical Model

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Description

InGaN semiconductors are promising candidates for high-efficiency next-generation thin film solar cells. In this work, we study the photovoltaic performance of single-junction and two-junction InGaN solar cells using a semi-analytical model. We analyze the major loss mechanisms in InGaN solar

InGaN semiconductors are promising candidates for high-efficiency next-generation thin film solar cells. In this work, we study the photovoltaic performance of single-junction and two-junction InGaN solar cells using a semi-analytical model. We analyze the major loss mechanisms in InGaN solar cell including transmission loss, thermalization loss, spatial relaxation loss, and recombination loss. We find that transmission loss plays a major role for InGaN solar cells due to the large bandgaps of III-nitride materials. Among the recombination losses, Shockley-Read-Hall recombination loss is the dominant process. Compared to other III-V photovoltaic materials, we discovered that the emittance of InGaN solar cells is strongly impacted by Urbach tail energy. For two- and multi-junction InGaN solar cells, we discover that the current matching condition results in a limited range of top-junction bandgaps. This theoretical work provides detailed guidance for the design of high-performance InGaN solar cells.

Date Created
2016-06-01
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Research on the Relationship between Integrity and Market Economy in China

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Description
The discussion on the question of integrity has a long history. It is regarded as an important research proposition in the fields of Chinese and Western philosophy, law, sociology, ethics, management and economics. Even though the research results are combined

The discussion on the question of integrity has a long history. It is regarded as an important research proposition in the fields of Chinese and Western philosophy, law, sociology, ethics, management and economics. Even though the research results are combined with each other for reference, there is still a lack of comprehensive analysis and empirical study on integrity. In the process of transition from planned economy to market economy, a series of problems have arisen. The problem of dishonesty has caused huge losses to the society as a whole. Therefore, it is of great theoretical and practical importance to conduct a quantitative analysis on the topic of trustworthiness, and investigate the relationship between trustworthiness and the economy.

This paper adopts a game theory model to analyze the reasons for corporate dishonesty, and the problem faced by the regulators. Based on the results from the model, we clarify the duties of various subjects (enterprises, governments and credit organizations) in the construction of a society with integrity.

Then, we analyze different cases of dishonesty and point out the channels through which the economy would be affected by the problem of dishonesty. (1) as an institution, integrity helps reduce the transaction cost and prompt market efficiency; (2) integrity serves as a production factor that influences the economy; (3) integrity will affect the economy by influencing the ability of small and medium enterprises to borrow.

Finally, after we establish the relationship between integrity and the market economy, we use survey data to conduct an empirical analysis on the development of integrity in China. The survey data allow us to build a cycle of integrity risk, and identify the current position in the cycle. Besides, we also compare the region difference regarding integrity, which supports the idea that integrity matters for the economic development.

Because the questionnaires are the only way to obtain the data that can be analyzed at present, the paper not only fills in the research gap caused by the lack of data, but also jumps out of the existing research methods, and enriches the empirical work for the study of integrity.
Date Created
2017
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Research on the Liquidity of China Treasury Futures Market

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Description
Given the "New Nine Measures" for capital market reform, a policy document issued by the State Council of China, the development of markets for interest rate derivatives, such as treasury futures, becomes an increasingly important task. Several shortcomings of the

Given the "New Nine Measures" for capital market reform, a policy document issued by the State Council of China, the development of markets for interest rate derivatives, such as treasury futures, becomes an increasingly important task. Several shortcomings of the existing treasury futures market have been noted: including low market liquidity, singular investor composition, restrict contract terms, and low hedging demand.

This study contributes to a better understanding of the treasury futures market by analyzing changes in China treasury futures market regulations and their impact on market liquidity of treasury futures. Found that compared with the mature market, China treasury futures market exists liquidity shortage, the trading system, market structure and the division of regulatory are factors which influence the liquidity of China treasury futures market.

This study found that reducing transaction costs for further optimization of the width and depth of China treasury futures market are not obvious by using quantitative analysis method, expanding the smallest change price can optimize the market depth, reducing transaction costs and expanding smallest change price can optimize the immediacy, volume and hosting amount. In addition, the bond market will also influence the treasury futures market, the price fluctuations and the morphology of the yield curve of bond market have significant influence on width, depth and holdings of market.

The system of China treasury futures market needs to be optimized by expanding the smallest change price and reducing transaction costs. The market structure needs to be optimized by establishing unified bond market and enriching investor structure.

These findings have significant theoretical and practical implications. The study also provides policy recommendations for the design and establishment of treasury futures market to the regulatory agencies.
Date Created
2016
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High-modulation-speed LEDs based on III-nitride

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Description
III-nitride InGaN light-emitting diodes (LEDs) enable wide range of applications in solid-state lighting, full-color displays, and high-speed visible-light communication. Conventional InGaN quantum well LEDs grown on polar c-plane substrate suffer from quantum confined Stark effect due to the large internal

III-nitride InGaN light-emitting diodes (LEDs) enable wide range of applications in solid-state lighting, full-color displays, and high-speed visible-light communication. Conventional InGaN quantum well LEDs grown on polar c-plane substrate suffer from quantum confined Stark effect due to the large internal polarization-related fields, leading to a reduced radiative recombination rate and device efficiency, which limits the performance of InGaN LEDs in high-speed communication applications. To circumvent these negative effects, non-trivial-cavity designs such as flip-chip LEDs, metallic grating coated LEDs are proposed. This oral defense will show the works on the high-modulation-speed LEDs from basic ideas to applications. Fundamental principles such as rate equations for LEDs/laser diodes (LDs), plasmonic effects, Purcell effects will be briefly introduced. For applications, the modal properties of flip-chip LEDs are solved by implementing finite difference method in order to study the modulation response. The emission properties of highly polarized InGaN LEDs coated by metallic gratings are also investigated by finite difference time domain method.
Date Created
2016
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The Impacts on Corporate Performance of the Banking Industry’s Compensation & Incentive Policy

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Description
Ever since the registration of private banks was deregulated in Taiwan in 1991, the sector has suffered significant decline in profitability. Facing such a dynamic sector yet vital to domestic economy, what should the banks do to successfully improve their

Ever since the registration of private banks was deregulated in Taiwan in 1991, the sector has suffered significant decline in profitability. Facing such a dynamic sector yet vital to domestic economy, what should the banks do to successfully improve their competiveness? As external changes are often unpredictable, the exploration and buildup of internal resources is a critical approach. This article focuses on how to effectively manage internal competition so as to upgrade business performance and accomplish organizational goals.

This article discusses the effects of the compensation system and employee incentives on business performance in banking in two areas. First of all, based on the statistics on the banking sector in Taiwan, it explores the regulating effects of different compensation systems on two conflicts in the industry. It also reviews the literature on Conflict Theory. Research shows that when people trust each other, they tend to accept a value statement different from theirs. And our research also shows that trust can minimize task conflict and relationship conflict between team members. Moreover, after identifying the role of compensation structure to trust and task conflict, this article further categorizes the structure into team performance reward and individual performance reward. Analysis points out that when the organization bases compensation payment on team performance reward, the relationship between trust and task conflict is higher than that on individual performance reward. That is, team performance reward better helps to reinforce such correlation compared to individual performance reward.

Second, the research studies different forms of employee incentives in Taiwan’s banking sector as well as resulting performance. During the studied period, the majority of the financial institutions preferred cash bonus. In addition, financial institutions also take other incentives. Cash bonus covered the highest percentage, followed by share bonus, treasury repo and transfer, and options in order. We study the ROEs under different incentives and conclude it is higher and more stable in the institutions offering multiple employee shares instead of single method. Whether the incentives are implemented also influence the level of net ROE.
Date Created
2016
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A Case Study of Executive Stock Compensation Design for The State-Owned Firms

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Description
Executive compensation design involving equity shares has been widely used in Europe, the United States and other developed countries where the capital markets are relatively mature. In China, due to the differences in industries, ownership structure, stages of enterprise development,

Executive compensation design involving equity shares has been widely used in Europe, the United States and other developed countries where the capital markets are relatively mature. In China, due to the differences in industries, ownership structure, stages of enterprise development, constraints faced by the firms, the executive compensation design using equity shares tends to vary accordingly. For the state-owned companies, the situations are more complex than others. This complexity has not been a focus of the past literature, particularly on the compensation contract design and its subsequent implementation. Based on Coase contract theorem, agency theory and human capital theory, I examined how different state-owned firms vary in their approaches on managerial stock compensation design using a case study approach. The thesis concludes with a summary of major findings and a discussion of policy implications.
Date Created
2016
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Research on Factors Influencing Individual’s Behavior of Energy Management

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Description
With the rapid rise of distributed generation, Internet of Things, and mobile Internet, both U.S. and European smart home manufacturers have developed energy management solutions for individual usage. These applications help people manage their energy consumption more efficiently. Domestic manufacturers

With the rapid rise of distributed generation, Internet of Things, and mobile Internet, both U.S. and European smart home manufacturers have developed energy management solutions for individual usage. These applications help people manage their energy consumption more efficiently. Domestic manufacturers have also launched similar products.

This paper focuses on the factors influencing Energy Management Behaviour (EMB) at the individual level. By reviewing academic literature, conducting surveys in Beijing, Shanghai and Guangzhou, the author builds an integrated behavioural energy management model of the Chinese energy consumers. This paper takes the vague term of EMB and redefines it as a function of two separate behavioural concepts: Energy Management Intention (EMI), and the traditional Energy Saving Intention (ESI).

Secondly, the author conducts statistical analyses on these two behavioural concepts. EMI is the main driver behind an individual’s EMB. EMI is affected by Behavioural Attitudes, Subjective Norms, and Perceived Behavioural Control (PBC). Among these three key factors, PBC exerts the strongest influence. This implies that the promotion of the energy management concept is mainly driven by good application user experience (UX). The traditional ESI also demonstrates positive influence on EMB, but its impact is weaker than the impacts arising under EMI’s three factors. In other words, the government and manufacturers may not be able to change an individual's energy management behaviour if they rely solely on their traditional promotion strategies. In addition, the study finds that the government may achieve better promotional results by launching subsidies to the manufacturers of these kinds of applications and smart appliances.
Date Created
2016
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