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91.
We design and fabricate ultra-high-quality (Q) photonic nanocavities in a symmetrically glass-clad silicon (Si) two-dimensional (2D) photonic crystal (PhC) structure. We theoretically investigate the dependence of the refractive index of the glass on the Q factors for asymmetric and symmetric structures. We show that the index-symmetric distribution of the glass is a critical factor to realize ultrahigh Q factors for glass-clad 2D PhC structures. We fabricate symmetrically glass-clad Si PhC nanocavities and achieve a record Q factor of 1×10(6), comparable with the highest Q factors of nanocavities in air-bridge structures. 相似文献
92.
93.
Jong Hyeuk Lim Kyong Nam Kim Min Hwan Jeon Jong Tae Lim Geun Young Yeom 《Plasma Chemistry and Plasma Processing》2011,31(3):507-515
Electrical and plasma properties of a U-shaped internal inductively coupled plasma (ICP) source with/without a Ni-Zn ferrite
module installed above the ICP antenna were investigated. By installing the ferrite module on the antenna, the increase of
plasma density and the decrease of plasma potential could be observed. The increase of plasma density was related to the efficient
inductive coupling to the plasma by concentrating the induced magnetic field between the antenna and the substrate. At 800 W
of ICP power and 20mTorr Ar, a high density plasma on the order of 4.5′1011/cm3 could be obtained. 相似文献
94.
Dr. Sung Lan Jeon Dr. Min Kyung Chae Eun Ju Jang Dr. Chulhyun Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(13):4217-4222
Iron oxide nanoparticles as contrast agents are reported to effectively improve magnetic resonance imaging of tissues and cells. In this work, cleaved iron oxide nanoparticles (CIONPs) were generated from hydrophobic FeO nanoparticles (HIONPs) by coating their surfaces with PEG‐phospholipids, oxidizing them under water, and slowly removing the residual FeO phase in phthalate buffer. The synthesized CIONPs showed good r2 values of up to 258 s?1 mM ?1. Thus, the CIONPs can be employed as vectors for drug delivery due to their unique structure with an empty inner space, which enables their use in a wide range of applications. 相似文献
95.
96.
S.-S. Bae D.K. Lim J.-I. Park J. Cheon I.C. Jeon S. Kim 《Applied Physics A: Materials Science & Processing》2005,80(6):1305-1310
We present a new strategy to fabricate a monolayer assembly of Br-terminated Co nanoparticles on functionalized Si surfaces by using chemical covalent bonding and microcontact printing method. Self-assembled monolayers (SAMs) of the Co nanoparticles formed on the hydroxyl-terminated Si surface exhibit two-dimensional island networks with locally ordered arrays via covalent linkage between nanoparticles and surface. On the other hand, SAMs of the nanoparticles on the aminopropyl-terminated Si surface show an individual and random distribution over an entire surface. Furthermore, we have fabricated striped architectures of Co nanoparticles using a combination of microcontact printing and covalent linkage. Microcontact printing of octadecyltrichlorosilane and selective covalent linkage between nanoparticles and functionalized Si surfaces lead to a hybrid nanostructure with selectively assembled nanoparticles stripes on the patterned functionalized Si surfaces. PACS 81.07.Ta; 61.46.+w; 81.16.Dn; 81.16.Be; 68.37.Hk; 82.80.Pv 相似文献
97.
98.
Kwangmin Park Eungjin Ahn Yu Jin Jeon Hyeonsik M. Cheong Jin Soak Kim Eun Kyu Kim Jungil Lee Young Ju Park Gun-Do Lee Euijoon Yoon 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):169
InAs quantum dots (QDs) were grown on InP substrates by metalorganic chemical vapor deposition. The width and height of the dots were 50 and 5.8 nm, respectively on the average and an areal density of 3.0×1010 cm−2 was observed by atomic force microscopy before the capping process. The influences of GaAs, In0.53Ga0.47As, and InP capping layers (5–10 ML thickness) on the InAs/InP QDs were studied. Insertion of a thin GaAs capping layer on the QDs led to a blue shift of up to 146 meV of the photoluminescence (PL) peak and an InGaAs capping layer on the QDs led to a red shift of 64 meV relative to the case when a conventional InP capping layer was used. We were able to tune the emission wavelength of the InAs QDs from 1.43 to 1.89 μm by using the GaAs and InGaAs capping layers. In addition, the full-width at half-maximum of the PL peak decreased from 79 to 26 meV by inserting a 7.5 ML GaAs layer. It is believed that this technique is useful in tailoring the optical properties of the InAs QDs at mid-infrared regime. 相似文献
99.
We present a simple modeling of random phase reference in holographic memory. The proposed model is analyzed by a statistical approach. Improvement on selectivity using random phase reference is shown in comparison with uniform phase plane wave reference and Gaussian beam reference. This simple and efficient model provides a physical insight and is verified by some experiments. 相似文献
100.
S.I. Jung J.J. Yoon H.J. Park Y.M. Park M.H. Jeon J.Y. Leem C.M. Lee E.T. Cho J.I. Lee J.S. Kim J.S. Son J.S. Kim D.Y. Lee I.K. Han 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):100
We investigate the effects of a thin AlAs layer with different position and thickness on the optical properties of InAs quantum dots (QDs) by using transmission electron microscopy and photoluminescence (PL). The energy level shift of InAs QD samples is observed by introducing the thin AlAs layer without any significant loss of the QD qualities. The emission peak from InAs QDs directly grown on the 4 monolayer (ML) AlAs layer is blueshifted from that of reference sample by 219 meV with a little increase in FWHM from 42–47 meV for ground state. In contrast, InAs QDs grown under the 4 ML AlAs layer have PL peak a little redshifted to lower energy by 17 meV. This result is related to the interdiffusion of Al atom at the InAs QDs caused by the annealing effect during growing of InAs QDs on AlAs layer. 相似文献