Browsing by Author "Ho, Wei-De"

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High-index sensitivity of surface mode in photonic crystal hetero-slab-edge microcavity
(2010-05-01)
Lu, Tsan-Wen
;
Hsiao, Yi-Hua
;
Ho, Wei-De
;
Lee, Po-Tsung
;
光電工程學系
We introduce a photonic crystal hetero-slab-edge microcavity design with surface mode, which is beneficial for optical index sensing. The simulated index sensitivity (R(n)) as high as 675 nm per refractive index unit (nm/RIU) variation is obtained with slab thickness of 180 nm. In experiments, single surface mode lasing action from a real device is observed. Based on the surface mode in this microcavity, high experimental R(n) value of 625 nm/RIU is achieved by detecting index variation in a CO(2) chamber with different gas pressures. (C) 2010 Optical Society of America
High-Q Photonic Crystal Hetero-Slab-Edge Microcavity Laser for Index Sensing
(2009)
Hsiao, Yi-Hua
;
Lu, Tsan-Wen
;
Ho, Wei-De
;
Lee, Po-Tsung
;
光電工程學系
We design a photonic crystal hetero-slab-edge microcavity sustaining surface mode with high quality factor similar to 5.4x10(5) and index sensitivity of 591 nm/refractive index unit by mode-gap effect. Lasing actions from real devices are also observed. (C)2009 Optical Society of America
Photonic crystal heteroslab-edge microcavity with high quality factor surface mode for index sensing
(2009-04-06)
Lu, Tsan-Wen
;
Hsiao, Yi-Hua
;
Ho, Wei-De
;
Lee, Po-Tsung
;
光電工程學系
In this report, we propose a photonic crystal heteroslab-edge microcavity design for optical index sensing, where the high quality (Q) surface mode is confined by mode-gap effect. By optimizing the barrier region of the microcavity, high Q factor of 6.6x10(5) is obtained in simulations. Lasing actions with high Q factor and low threshold of 6400 and 0.55 mW are obtained from the real devices. High index sensing response and small detectable index variation of 625 nm per refractive index unit and 3.6x10(-6) are obtained in simulations.
Thermal Properties of 12-Fold Quasi-Photonic Crystal Microcavity Laser With Size-Controlled Nano-Post for Electrical Driving
(2009-12-01)
Ho, Wei-De
;
Lu, Tsan-Wen
;
Hsiao, Yi-Hua
;
Lee, Po-Tsung
;
光電工程學系
In this report, we investigate the fabrication process of 12-fold quasi-photonic crystal microcavity with size-controlled nano-post beneath for electrically-driven structure by fine-tuning the wet-etching time. By finite-element method, we simulate and analyze the heat transfer behaviors of microcavities with different nano-post sizes and shapes. From the real devices, we obtain whispering-gallery (WG) single-mode lasing action with high measured quality factor of 8 250 and low threshold of 0.6 mW when the nano-post size is as large as 830 nm in diameter. By varying the substrate temperature, WG single-mode lasing action is still obtained when the substrate temperature is as high as 70 C. Besides, the lasing wavelength red-shift rate is also improved compared with the microcavity without nano-post beneath. By varying the pump condition, lasing action is still observed at room temperature when the pump duty cycle increases to 16.0%. Thus, for electrically-driven photonic crystal microcavity lasers, this nano-post can serve as current injection pathway and heat sink at the same time.
Thermal Properties of Post-Size Controlled 12-Fold Quasi-Photonic Crystal Microcavity for Electrically-Driving
(2009)
Ho, Wei-De
;
Hsiao, Yi-Hua
;
Lu, Tsan-Wen
;
Lee, Po-Tsung
;
光電工程學系
We fabricate 12-fold quasi-photonic crystal microcavity with size-controlled post for electrically-driven structure by fine-tuning wet-etching time. Improved thermal properties of microcavities with different post sizes are investigated both in finite-element method simulations and experiments. (c) 2009 Optical Society of America