• JSTS:Journal of Semiconductor Technology and Science
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• 제7권2호
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• pp.102-109
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• 2007

We propose and experimentally demonstrate a ring resonator with sharp U-turns fabricated on a silicon-on-insulator (SOI) substrate; the resonator was designed as a key part of an optical, dynamic data storage device. We discuss the optical properties of the fabricated ring resonator from the viewpoint of equi-frequency-contour behavior in a dispersion space. We successfully characterize its optical characteristics on the basis of photonic crystal physics. It is suggested that the photonic ring resonator will be applicable to optical, dynamic memory devices for optical communication systems.

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 제11회 정기총회 및 00년 동계학술발표회 논문집
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• pp.260-261
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• 2000

광결정(photonic crystal)은 빛의 파장 크기 정도의 격자 상수를 지닌 1차원, 2차원, 또는 3차원의 주기적인 구조이다. 광결정에는 광밴드갭(photonic bandgap)이라는 빛의 자발 방출이 억제된 진동수의 영역이 존재하는데, 이 영역을 이용하여 빛의 자발 방출을 조절하고 빛의 흐름을 제어할 수 있다. $^{[1]}$ 지난 10여년간 2차원, 3차원의 광결정 구조에 대한 연구가 많이 이루어져 왔는데, 최근에는 슬랩 도파관(slab waveguide)에 2차원 광결정을 만든 구조에 대한 연구가 활발하게 진행중이다. 이 구조는 평면 방향으로는 광밴드갭 효과로 광모드를 가둘 수 있고 수직 방향으로는 전반사를 이용하여 모드를 가둘 수 있어서 3차원적인 모드 confinement 효과를 얻을 수 있다. [그림 1]의 (a)에 air-bridge 형태의 2차원 광결정 슬랩(photonic crystal slab) 구조를 도식적으로 나타내었고, (b)에는 본 연구실에서 제작한 구조 표면의 scanning electron micrograph을 나타내었다. 현재 몇몇 연구 그룹에서 이와 같은 광결정 슬랩 구조를 이용한 반도체 레이저를 실현하는데 성공하였다.$^{[2,3]}$ (중략)

• 한국진공학회지
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• 제12권S1호
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• pp.15-16
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• 2003

3-D photonic band-gap structures are fabricated from dielectric colloidal polystyrene beads through a centrifuge method. The fabricated photonic crystals exhibit opalescent colors under white light and show a clear diffraction peak dependent on the incident angle of the light beam. Also the scanning electron microscope image was taken to verify the face-centered cubic crystal structure. Bragg's law and Snell's law are employed to describe the position of angle resolved diffraction peaks. It was shown that the optically deduced effective refractive index and lattice constants were in good agreement with the crystal structure identified by scanning electron microscope.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.243-252
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• 2002

We propose a new concept: that of photonic crystal phosphors (PCPs) for display and phosphor related applications. It is well known that microcavities with dimensions comparable to the emitting wavelength strongly enhance light-matter interactions, resulting in a significant increase in spontaneous emission rate, which can be directly translated into enhancement in phosphor efficiency. In recent simulations we have demonstrated that when a microcavity is formed in a nano-phosphor structure, the luminescence band is modified, and can be made spectrally sharp and tunable by engineering the geometry/material properties of the cavity and the surrounding photonic crystal lattice. New phosphor material structures based on photonic crystals are proposed. Applications to thin film EL phosphors and particle phosphors are discussed. Additionally, economic methods of synthesizing and incorporating PCPs into current display applications are proposed.

• 한국통신학회논문지
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• 제26권12B호
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• pp.1754-1757
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• 2001

본 논문에서는 IMT-2000, 무선LAN, PCS 대역인 R-band에서 Coplanar waveguide (CPW)와 Photonic Bandgap (PBG)을 이용한 증폭기를 설계 및 제작하였다. 기존 마이크로스트립을 이용한 증폭기에만 적용되던 PBG 기술을 처음으로 CPW를 이용한 증폭기에 적용하여 출력효율 및 IMD를 측정하였다. PBG구조는 매칭 네트웍구성을 위해 최적화되었으며 이로인해 입출력 반사손실이 최소화 되도록 PBG 구조가 정합되었다. 측정결과 CPW구조에 새롭게 적용퇸 PBG구조를 이용하여 동일 IMD에 대해 15%의 출력효율과 동일 출력에 대해 IMD 4.5dB 향상을 얻을 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1933-1935
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• 2002

In this paper, we present a study of the structure and electro-optic behavior of hybrid liquid-crystal-silica sphere composite photonic crystals, formed by filling the (26% by volume) void space of fee (face centered cubic) silica opals infiltrated with a nematic liquid crystal. Three dimensional photonic crystals of visible range were fabricated via a self assembly method of silica spheres of submicron diameter. The expected fee structure was confirmed by scanning electron microscopy (SEM) of the dehydrated crystal with glass removed. The photonic crystal exhibited significant electric-field-induced shift of the optical Bragg reflection peak when the liquid crystal has the long molecular axis oriented parallel to the sphere surfaces.

• 한국광학회:학술대회논문집
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• 한국광학회 2003년도 제14회 정기총회 및 03년 동계학술발표회
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• pp.38-39
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• 2003

The GaAs semiconductor whispering gallery modes, produced in the peripheral Rayleigh band region of W／sub Rayleigh／ ＝ (${\Phi}$／2)( 1-n／sub eff／n), exhibit novel properties of ultralow thresholds open to nano-ampere regime associated with photonic quantum ring (PQR) production (Fig 1 (a)). The PQR phenomena are associated with a photonic field-driven phase transition of quantum well(QW)-to-quantum wire (QWR) and hence the photonic (non-de Broglie) quantum corral effects, on the Rayleigh cavity confined carriers in dynamic steady state, occur as schematically shown in Fig 1. (omitted)

• 한국광학회:학술대회논문집
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• 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
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• pp.2-3
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• 2001

Characteristics of two-dimensional slab photonic crystal lasers will be summarized. Room temperature c.w operation is demonstrated at 1.6 $\mu\textrm{m}$ by using InGaAsP slab-waveguide triangular photonic crystal on top of wet-oxidized aluminum oxide. Recently, 2-D PBG structures have attracted a great deal of attention due to their simplicity in fabrication and theoretical study as compared to the three-dimensional counterparts [1]. Air-guided 2-D slab PBG lasers were reported by Caltech group (2). However, this air-slab structure is mechanically fragile and thermally unforgiving. Therefore, a new structure that can remove this thermal limitation is dearly sought after for 2-D PBG laser to have practical meaning. In this talk, we report room-temperature continuous operation of 2-D photonic bandgap lasers that are thermally and mechanically stable.(omitted)

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.69-70
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• 2006

Air-guided single-mode propagation of THz radiation in a photonic crystal waveguide (PCW) has been experimentally demonstrated for the first time. The PCW has been fabricated by introducing an air defect at the center of an air/Si 1D photonic crystal. By using a THz time-domain spectroscopic technique, we have experimentally shown that the guiding mechanism of the air-guiding PCW is the photonic bandgap effect.

• Journal of the Optical Society of Korea
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• 제16권3호
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• pp.282-287
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• 2012

In this paper, we have proposed a principle to design a compact and temperature independent electro-optic switch based on a slotted photonic crystal directional coupler (SPCDC). Infiltration of the slotted silicon photonic crystal with polymer enhances the slow light and decreases the switching length, whereas the different signs of thermo-optic coefficients of the polymer and silicon make the proposed switch stable within $25^{\circ}C$ to $85^{\circ}C$ temperature range. The SPCDC structure is modified to increase poling efficiency of the polymer in the slot and to flatten the dispersion diagram of the even mode to minimize the switching length.