Browsing by Issue Date, starting with "2018-11-19"

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Manipulation of the dephasing time by strong coupling between localized and propagating surface plasmon modes
(2018-11-19)
Yang, Jinghuan
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Sun, Quan
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Ueno, Kosei
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Shi, Xu
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Oshikiri, Tomoya
Strong coupling between two resonance modes leads to the formation of new hybrid modes exhibiting disparate characteristics owing to the reversible exchange of information between different uncoupled modes. Here, we realize the strong coupling between the localized surface plasmon resonance and surface plasmon polariton Bloch wave using multilayer nanostructures. An anticrossing behavior with a splitting energy of 144 meV can be observed from the far-field spectra. More importantly, we investigate the near-field properties in both the frequency and time domains using photoemission electron microscopy. In the frequency domain, the near-field spectra visually demonstrate normal-mode splitting and display the extent of coupling. Importantly, the variation of the dephasing time of the hybrid modes against the detuning is observed directly in the time domain. These findings signify the evolution of the dissipation and the exchange of information in plasmonic strong coupling systems and pave the way to manipulate the dephasing time of plasmon modes, which can benefit many applications of plasmonics.
Large anomalous Nernst effect in thin films of the Weyl semimetal Co2MnGa
(2018-11-19)
Reichlova, Helena
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Schlitz, Richard
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Beckert, Sebastian
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Swekis, Peter
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Markou, Anastasios
The magneto-thermoelectric properties of Heusler compound thin films are very diverse. Here, we discuss the anomalous Nernst response of Co2MnGa thin films. We systematically study the anomalous Nernst coefficient as a function of temperature, and we show that unlike the anomalous Hall effect, the anomalous Nernst effect in Co2MnGa strongly varies with temperature. We exploit the on-chip thermometry technique to quantify the thermal gradient, which enables us to directly evaluate the anomalous Nernst coefficient. We compare these results to a reference CoFeB thin film. We show that the 50-nm-thick Co2MnGa films exhibit a large anomalous Nernst effect of -2 mu V/K at 300 K, whereas the 10-nm-thick Co2MnGa film exhibits a significantly smaller anomalous Nernst coefficient despite having similar volume magnetizations. These findings suggest that the microscopic origin of the anomalous Nernst effect in Co2MnGa is complex and may contain contributions from skew-scattering, side-jump, or intrinsic Berry phase. In any case, the observed anomalous Nernst coefficient of -2 mu V/K at 300 K is large compared to the values measured in other thin films and makes this material system a very promising candidate for efficient spin-caloritronic devices. Published by AIP Publishing.
Search for a time-varying electron antineutrino signal at Daya Bay
(2018-11-20)
Adey, D.
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An, F. P.
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Balantekin, A. B.
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Band, H. R.
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Bishai, M.
A search for a time-varying (nu) over bar (e) signal was performed with 621 days of data acquired by the Daya Bay Reactor Neutrino Experiment over 704 calendar days. The time spectrum of the measured (nu) over bar (e) flux normalized to its prediction was analyzed with a Lomb-Scargle periodogram, which yielded no significant signal for periods ranging from 2 hours to nearly 2 years. The normalized time spectrum was also fit for a sidereal modulation under the Standard Model Extension (SME) framework to search for Lorentz and CPT violation (LV-CPTV). Limits were obtained for all six flavor pairs (e) over bar(mu) over bar, (e) over bar(tau) over bar, (mu) over bar(tau) over bar, (e) over bar(e) over bar, (mu) over bar(mu) over bar and (tau) over bar(tau) over bar by fitting them one at a time, constituting the first experimental constraints on the latter three. Daya Bay's high statistics and unique layout of multiple directions from three pairs of reactors to three experimental halls allowed the simultaneous constraint of individual SME LV-CPTV coefficients without assuming others contribute negligibly, a first for a neutrino experiment.
交大e-News第267期-張懋中校長榮膺HKN Vladimir Karapetoff 科技終身成就獎章
(2018-11-20)
國立交通大學秘書室
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Secretariat
Interactions of BDNF Val66Met Polymorphism and Menstrual Pain on Brain Complexity
(2018-11-20)
Low, Intan
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Kuo, Po-Chih
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Tsai, Cheng-Lin
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Liu, Yu-Hsiang
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Lin, Ming-Wei
The irregularity and uncertainty of neurophysiologic signals across different time scales can be regarded as neural complexity, which is related to the adaptability of the nervous system and the information processing between neurons. We recently reported general loss of brain complexity, as measured by multiscale sample entropy (MSE), at pain-related regions in females with primary dysmenorrhea (PDM). However, it is unclear whether this loss of brain complexity is associated with inter-subject genetic variations. Brain-derived neurotrophic factor (BDNF) is a widely expressed neurotrophin in the brain and is crucial to neural plasticity. The BDNF Val66Met single-nucleotide polymorphism (SNP) is associated with mood, stress, and pain conditions. Therefore, we aimed to examine the interactions of BDNF Val66Met polymorphism and long-term menstrual pain experience on brain complexity. We genotyped BDNF Val66Met SNP in 80 PDM females (20 Val/Val, 31 Val/Met, 29 Met/Met) and 76 healthy female controls (25 Val/Val, 36 Val/Met, 15 Met/Met). MSE analysis was applied to neural source activity estimated from resting-state magnetoencephalography (MEG) signals during pain-free state. We found that brain complexity alterations were associated with the interactions of BDNF Val66Met polymorphism and menstrual pain experience. In healthy female controls, Met carriers (Val/Met and Met/Met) demonstrated lower brain complexity than Val/Val homozygotes in extensive brain regions, suggesting a possible protective role of Val/Val homozygosity in brain complexity. However, after experiencing long-term menstrual pain, the complexity differences between different genotypes in healthy controls were greatly diminished in PDM females, especially in the limbic system, including the hippocampus and amygdala. Our results suggest that pain experience preponderantly affects the effect of BDNF Val66Met polymorphism on brain complexity. The results of the present study also highlight the potential utilization of resting-state brain complexity for the development of new therapeutic strategies in patients with chronic pain.
Holographic entanglement entropy in boundary conformal field theory
(2018-11-21)
Chang, En-Jui
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Chou, Chia-Jui
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Yang, Yi
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電子物理學系
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Department of Electrophysics
We study the holographic entanglement entropy in a (d + 1)-dimensional boundary quantum field theory at both the zero and finite temperature. The phase diagrams for the holographic entanglement entropy at various temperatures are obtained by solving the entangled surfaces in the different homology. We also verify the Araki-Lieb inequality and illustrate the entanglement plateau.
STEREOSCOPIC IMAGING METHOD AND DEVICE
(2018-11-22)
Tian-Sheuan CHANG
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Yi-Chun CHEN
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Jen-Hui CHUANG
A stereoscopic imaging method includes: acquiring a convergence disparity value, which corresponds to a screen position at which a viewer is looking, from an original disparity map corresponding to first and second images that correspond to different viewing angles; generating a disparity transformation model based on the convergence disparity value and viewer-related information; transforming the original disparity map into a transformed disparity map based on the disparity transformation model; and synthesizing the first and second images into a stereoscopic image based on the transformed disparity map.
Integral Method Analysis of Electroabsorption Spectra and Electrophotoluminescence Study of (C4H9NH3)(2)Pbl(4) Organic-Inorganic Quantum Well
(2018-11-22)
Kattoor, Vidya
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Awasthi, Kamlesh
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Jokar, Efat
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Diau, Eric Wei-Guang
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Ohta, Nobuhiro
Electric-field-induced changes in absorption and photoluminescence (PL) spectra and in PL decay profile have been measured for two-dimensional hybrid organic inorganic halide perovskite semiconductor, ((C4H9NH3)(2)Pbl(4)) (N1). Electroabsorption (E-A) spectra observed at room temperature and at a low temperature of 45 K were analyzed by assuming the Stark shift, and the magnitudes of the change in electric dipole moment and polarizability following photoexcitation were determined. The strong signal observed in the E-A spectra at 45 K was interpreted in terms of the weak absorption band which shows extremely large Stark shift resulting from the large change in polarizability following photoexcitation. Electrophotoluminescence spectra of this compound, that is, field-induced change in PL spectra, show that PL of N1 is quenched by the application of electric field. Field effects on PL decay profiles show that the quenching results both from the field-induced decrease of the population of the emitting state following photoexcitation and from the field-induced lifetime shortening caused by the enhancement of the nonradiative decay rate at the emitting state. At a low temperature of 45 K, two exciton emissions, each of which originates from different phase, appear, and both emissions are quenched by the applied electric field with different efficiencies from each other. It is also found that trap emissions observed at low temperature in the wavelength region longer than the sharp exciton bands show more efficient field-induced quenching than that of the exciton emissions, suggesting that energy transfer from the photoexcited state to trapped states is decelerated by the applied electric field.
A Water-Soluble NaCMC/NaPAA Binder for Exceptional Improvement of Sodium-Ion Batteries with an SnO2-Ordered Mesoporous Carbon Anode
(2018-11-23)
Patra, Jagabandhu
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Rath, Purna Chandra
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Li, Chi
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Kao, Hsien-Ming
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Wang, Fu-Ming
SnO2@CMK-8 composite, a highly promising anode for Na-ion batteries (NIBs), was incorporated with polyvinylidene difluoride (PVDF), sodium carboxymethylcellulose (NaCMC), sodium polyacrylate (NaPAA), and NaCMC/NaPAA mixed binders to optimize the electrode sodiation/desodiation properties. Synergistic effects between NaCMC and NaPAA led to the formation of an effective protective film on the electrode. This coating layer not only increased the charge-discharge Coulombic efficiency, suppressing the accumulation of solid-electrolyte interphases, but also kept the SnO2 nanoparticles in the CMK-8 matrix, preventing the agglomeration and removal of oxide upon cycling. The adhesion strength and stability towards the electrolyte of the binders were evaluated. In addition, the charge-transfer resistance and apparent Na+ diffusion of the SnO2@CMK-8 electrodes with various binders were examined and post-mortem analyses were conducted. With NaCMC/NaPAA binder, exceptional electrode capacities of 850 and 425 mAh g(-1) were obtained at charge-discharge rates of 20 and 2000 mA g(-1), respectively. After 300 cycles, 90 % capacity retention was achieved. The thermal reactivity of the sodiated electrodes was studied by using differential scanning calorimetry. The binder effects on NIB safety, in terms of thermal runaway, are discussed.
草地x藝術　交大西區藝術節
(2018-11-25)
彭姿敏
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郭玟妤
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Department of Communication and Technology
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傳播與科技學系
2018交大西區藝術節配合校慶60週年，聯合清交草地音樂季，舉辦一系列藝文活動，帶領大家體會校園藝文生態之美。
台灣補習教育之現象　
(2018-11-25)
林函諭
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Department of Communication and Technology
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傳播與科技學系
關於補習這件事，已聚訟紛紜多年。補習教育在台灣究竟該何以得解？
胡子睿　用手語編織的夢想
(2018-11-25)
廖庭歡
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Department of Communication and Technology
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傳播與科技學系
胡子睿拍攝了兩部手語舞蹈影片，分別是《成全》、《半島鐵盒》，在網路上造成廣大迴響，手語對他來說，是生命無法減去的熱愛。
你有拖延症嗎？
(2018-11-25)
李欣秝
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Department of Communication and Technology
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傳播與科技學系
每個人的人生幾乎都有拖延的情形發生，不管你是學生、上班族或是大老闆，大家都可能因為某些原因而不斷地在拖延，以下將探討拖延發生的原因和可能的解決方法。
設計師之路從襪子開始　楊慧淳
(2018-11-25)
汪彥彤
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Department of Communication and Technology
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傳播與科技學系
毅然決然放棄薪水穩定的公職，楊慧淳用不起眼的襪子設計出更精彩的人生。
織繡、布匹與夢　「布博」
(2018-11-25)
李庭安
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Department of Communication and Technology
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傳播與科技學系
2018年11月10號至11號，布博（nunohaku）於華山文化創意產業園區開展，在色彩、織繡與布之間，裁紉出創作者的夢。
觀光更自由？網約導遊到此一遊
(2018-11-25)
呂奕廷
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Department of Communication and Technology
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傳播與科技學系
近年來中國興起的網約導遊，顛覆以往由旅行社指派的模式，讓導遊得以自由執業。究竟在這一波新的旅遊模式下，台灣應該如何看待並走出導遊觀光的未來？
總編輯的話
(2018-11-25)
陳儀軒
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Department of Communication and Technology
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傳播與科技學系
本期為喀報的第303期，共計九篇文章，以人物故事為主。本期頭題為梁書瑜的〈吳淑美　融合教育的幕後推手〉，人物介紹有深度，且文字充滿溫度，字裡行間中能見人物的特質與經歷，文情並茂，讀來十分親切。
TAOS based Cu/TiW/IGZO/Ga2O3/Pt bilayer CBRAM for low-power display technology
(2018-11-25)
Gan, Kai-Jhih
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Liu, Po-Tsun
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Chiu, Yu-Chuan
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Ruan, Dun-Bao
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Chien, Ta-Chun
We demonstrate the characteristics of a conductive-bridging random access memory (CBRAM) with Cu/TiW/InGaZnO/Ga2O3/Pt stack structure. The addition of a thin metal-oxide layer (4.5 nm-thick Ga2O3) in the bottom of the CBRAM device significantly increases the off-state resistance (Rom') and the memory window. The IGZO bi-layer CBRAM shows the excellent memory performances, such as low operation current (down to 50 A), high on/off resistance ratio (> 10(3)), high switching endurance (up to 10(3) cycles) and the capability of multi-level tuning. Meanwhile, high thermal stability was also achieved. Three decades of resistance window is constantly maintained beyond 10(4)s at 85 degrees C. The resistive switching stability and electrical uniformity of bi-layer IGZO/Ga2O3 CBRAM device are obviously enhanced as compared with the one only with a single layer of IGZO film. These results have given a great potential for the transparent amorphous oxide semiconductor (TAOS)-based material utilizing in CBRAM stacks and integrating into the display circuits for future memory-in-pixel applications.
吳淑美　融合教育的幕後推手
(2018-11-25)
梁書瑜
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Department of Communication and Technology
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傳播與科技學系
融合教育是將普通生和特殊生放在一起上課的教學模式。在這，普通孩子是大天使，特殊孩子是小天使，他們坐在同一間教室裡，不分你我，一起生活。
掙脫深淵　綻放新生——陳慧珠
(2018-11-25)
王允妍
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Department of Communication and Technology
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傳播與科技學系
「人生就像寫故事一樣，上半部寫得非常非常地爛，但我下半部人生是越寫越精彩！」