Advanced search options

Advanced Search Options 🞨

Browse by author name (“Author name starts with…”).

Find ETDs with:

in
/  
in
/  
in
/  
in

Written in Published in Earliest date Latest date

Sorted by

Results per page:

Sorted by: relevance · author · university · dateNew search

You searched for +publisher:"NSYSU" +contributor:("Hao-Hsiung Lin"). Showing records 1 – 3 of 3 total matches.

Search Limiters

Last 2 Years | English Only

No search limiters apply to these results.

▼ Search Limiters


NSYSU

1. Feng, Jui-yang. N-type Modulation-Doped InGaAlAs/InP Strain-Balanced Multiple Quantum Wells for Photonic Integrated Circuits.

Degree: PhD, Electro-Optical Engineering, 2008, NSYSU

In this work, we have reported the design, MBE-growth and fabrication of strain-balanced n-type modulation-doped (MD) InGaAlAs/InGaAs multiple quantum wells laser/SOAs on InP. The quantum well contains a lattice-matched InGaAs core, a compressive-strained InGaAs padding, and a tensile-strained InGaAlAs spacer. Two kinds of samples having similar structure but different fundamental transition wavelength of 1.55 μm and 1.48 μm are separately prepared for investigating their characteristics in optical amplification under forward bias and electro-absorption under reversed bias. Also, the technique of growing high-quality InGaAlAs with solid-source molecular beam epitaxy has been established and the resulting InGaAlAs bulk and QWs samples are extensively characterized by double-crystal X-ray diffraction, transmission electron microscopy, electroluminescence, and photoluminescence measurements. For λ = 1.55 μm samples, ridge-waveguide lasers of Fabry-Perot (FP) type and tilted-end-facet (TEF) type were fabricated by a new developed multi-step wet-etching process. When injection current density > 20A/cm2, electroluminescence spectra show higher optical gain for the quantum well e1-hh2 transition at λ = 1460 nm than the e1-hh1 transition at λ = 1550 nm. The FP laser shows a lasing peak of λ = 1514 nm at threshold. Additional lasing wavelength at λ =1528 nm and 1545 nm were observed sequentially as the injection current increased. However, for the TEF laser, only the emission at λ = 1511 nm was observed. These TE-polarized lasing wavelengths are consistent with the δ-like absorption peaks in photocurrent spectra. The lasing performance is possible attributed to optical transitions within quantum dots/wires which are formed by the strain-field profile and alloy segregation/migration. For λ = 1.48 μm samples, the differential absorption spectroscopy, which measures the change of transmission (ÎT/T) in the presence of electric field, is used to study the electro-absorption modulation behavior of MD-SOAâs. A sample with n-type modulation-doping amounting to a sheet density of 3.5 à 1011 cm-2 per QW and combining with a hole-stopping barrier represents the largest chirp parameter (În/Îk) under reversed bias, which offers an excellent platform to realize electro-refractive devices with larger refractive index changes (În) but lower differential absorption (Îα) near λ = 1.55 μm, which is also our interested region of operation. In addition, we have succeeded in reducing the length of conventional constant-width multimode interference (MMI) coupler of K = 0.15 and 0.28 more than 32% by a novel stepped-width design concept. By extending the stepped-with idea, we show that it is possible to obtain 2x2 waveguide couplers with new power splitting ratios of 7%, 64%, 80% and 93% for cross coupling by cascading two short MMI sections. We further realize freely chosen power splitting ratio by interconnecting a pair of unequal-width waveguides as the phase-tuning section into the middle of two short MMI sections. These… Advisors/Committee Members: Tsong-Sheng Lay (committee member), Hao-Hsiung Lin (chair), Sheng-Lung Huang (chair), Shoou-Jinn Chang (chair), Hao-chung Kuo (chair), Wood-Hi Cheng (chair), Pochi Yeh (chair), Yi-Jen Chiu (chair), Ching-Ting Lee (chair).

Subjects/Keywords: Multiple Quantum Well; SOA; InGaAlAs; N-type Modulation-Doped; Laser; Arbitrary Power Splitting Ratio; InP; Multimode Interference Coupler; Strain-balanced

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Feng, J. (2008). N-type Modulation-Doped InGaAlAs/InP Strain-Balanced Multiple Quantum Wells for Photonic Integrated Circuits. (Doctoral Dissertation). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0804108-200322

Chicago Manual of Style (16th Edition):

Feng, Jui-yang. “N-type Modulation-Doped InGaAlAs/InP Strain-Balanced Multiple Quantum Wells for Photonic Integrated Circuits.” 2008. Doctoral Dissertation, NSYSU. Accessed April 06, 2020. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0804108-200322.

MLA Handbook (7th Edition):

Feng, Jui-yang. “N-type Modulation-Doped InGaAlAs/InP Strain-Balanced Multiple Quantum Wells for Photonic Integrated Circuits.” 2008. Web. 06 Apr 2020.

Vancouver:

Feng J. N-type Modulation-Doped InGaAlAs/InP Strain-Balanced Multiple Quantum Wells for Photonic Integrated Circuits. [Internet] [Doctoral dissertation]. NSYSU; 2008. [cited 2020 Apr 06]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0804108-200322.

Council of Science Editors:

Feng J. N-type Modulation-Doped InGaAlAs/InP Strain-Balanced Multiple Quantum Wells for Photonic Integrated Circuits. [Doctoral Dissertation]. NSYSU; 2008. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0804108-200322


NSYSU

2. Chuang, Kuei-ya. Vertically Coupled InGaAs Quantum Dots.

Degree: PhD, Electro-Optical Engineering, 2012, NSYSU

We have investigated the polarization effect of optical process in the vertically coupled InGaAs quantum dots (QDs) triple layers by varying the thickness of GaAs spacer layer. The TE/TM ratio for the ground state emission decreases from near 4 to 1.5 as the spacer thickness (d) decreases from 40 nm to 5 nm. And, the TE polarization (in-plane polarization) is anisotropic with a stronger component along [01-1] direction. P-type modulation doping further decreases the TE/TM ratio to r = 1.2 for the strong vertical coupling QDs structure of 5-nm spacer. Then, using a cross-sectional transmission electron microscopy directly reveals the InGaAs QDs of 5-nm spacer well aligned along the growth direction. From the electroluminescence (EL) and differential absorption (Îα) experiments, the higher optical gain and absorption change for the excited state suggest that the e2-hh transition has higher oscillator strength for the vertically coupled QDs. We also investigate for the triple-layer InGaAs vertically coupled quantum dots (VCQDs) by adding modulation doping (MD) in the 5-nm GaAs spacer layers. In addition to the QDs fundamental and excited transitions, a coupled-state transition is observed for the VCQDs. For the VCQDs of p-type MD, the optical transitions at ground state and coupled state are enhanced by the improvement of hole capture for the valence subbands. For the VCQDs of n-type MD, the main absorption change occurs at the coupled state, consistent with the dominant emission peak observed in EL spectra. For GaAs-based solar cells application, in order to enhance absorption at infrared range for GaAs-based solar cells, multi-stack InGaAs VCQDs of 5-nm GaAs spacers are grown in the active region. Due to the strong vertical coupling between QDs would promote quantum efficiency. We have investigated the photovoltaic response for the solar cells by increasing the layer numbers of VCQDs. The device of nine-layer InGaAs VCQDs shows an enhanced short-circuit current density (Jsc) of 10.5 mA/cm2. The value is increased by 42% compared to GaAs reference device. However, the open-circuit voltage (Voc) is reduced from 0.88 V to 0.54 V. Then, we change the GaAs spacer thickness of coupled In0.75Ga0.25As QDs, and investigated the effects on photovoltaic response. For the sample of d =10 nm shows the best performance of current density (Jsc~24 mA/cm2) and efficiency (h~10.6%). The Jsc and h are increases by 55% and 112% more than the device without QDs, respectively. Advisors/Committee Members: Min-Hsiung Shih (chair), Wood-Hi Cheng (chair), Kuo-Jui Lin (chair), Yi-Jen Chiu (chair), Chien-Chung Lin (chair), Jau-Sheng Wang (chair), Ming-Hua Mao (chair), Tsong-Sheng Lay (committee member), Hao-Hsiung Lin (chair).

Subjects/Keywords: Modulation doping; Coupling; Quantum dot; InGaAs; Solar cell

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Chuang, K. (2012). Vertically Coupled InGaAs Quantum Dots. (Doctoral Dissertation). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0731112-122123

Chicago Manual of Style (16th Edition):

Chuang, Kuei-ya. “Vertically Coupled InGaAs Quantum Dots.” 2012. Doctoral Dissertation, NSYSU. Accessed April 06, 2020. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0731112-122123.

MLA Handbook (7th Edition):

Chuang, Kuei-ya. “Vertically Coupled InGaAs Quantum Dots.” 2012. Web. 06 Apr 2020.

Vancouver:

Chuang K. Vertically Coupled InGaAs Quantum Dots. [Internet] [Doctoral dissertation]. NSYSU; 2012. [cited 2020 Apr 06]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0731112-122123.

Council of Science Editors:

Chuang K. Vertically Coupled InGaAs Quantum Dots. [Doctoral Dissertation]. NSYSU; 2012. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0731112-122123


NSYSU

3. Tzeng, Te-En. InGaAs Quantum Dots grown by Molecular Beam Epitaxy.

Degree: Master, Electro-Optical Engineering, 2011, NSYSU

In this thesis, we have reported the MBE growth, design, and fabrication of the InGaAs quantum dots (QDs) laser/semiconductor optical amplifier, broadband QDs structure, coupled double cavity structure for terahertz emission on GaAs substrate. The emission wavelengths of the strain-induced S-K growth mode QDs structures are adjusted through the composition of QDs and strain-compensated capping layer. Also, the technique of growing high quality InGaAs QDs with solid source molecular beam epitaxy has been established and characterized by double crystal X-ray diffraction, transmission electron microscopy, photoluminescence, electroluminescence measurements. For 1.3μm QDs laser samples, ridge waveguide lasers of the Fabry-Perot (FP) type are fabricated by wet-etching process. From the QDs laser L-I curve, the e2-hh2 transition at λ =1160nm have larger optical gain than e1-hh1 transition at λ =1220nm. The FP laser with 0.6μm cavity length shows a lasing peak of 1160nm at threshold. As the cavity length increase to 2μm, the lasing peak red shift to 1220nm (closed to ground state emission wavelength). This energy band gap transition phenomenon is obvious especially in the QDs laser with quantum well (QW) structure. When the injection current increase, two lasing peaks at λ= 1160 and 1175nm are observed sequentially. This unique lasing behavior is shown to be consistent with carriers localized in noninteracting dots. For the application of 1.3μm light source, we optimum the growth condition for different needs in optical coherent tomography (OCT) light source, tandem solar cell, terahertz emission light source, etc. For the super luminescence diode (SLED) in OCT, we design multi-stacked asymmetric QDs structure (AMQD), QDs in the well structure (DWell), Dwell with p-doping in well structure to investigate the carrier recombination condition and bandwidth. Comparing with 5 structures in this study, the Dwell with p-doping in well structure has a maximum EL bandwidth exceed 198nm. The large bandwidth is attributed to the QW which increases the carrier capture rate and the p-doping which provide the efficient holes in valance band. This structure provides an excellent SLED light source solution to replace the existing program. For the tandem solar cell, we use the multi-stack QDs to compose broadband absorption in 1eV range. In order to avoid the degradation in the open circuit voltage, we use InGaAs QW to reduce the QDs strain. We observed the doping effect on the built in field through the photo-reflectance measurements. For the better photocurrent collection, we use p-doping in the QW to increase the built-in field intensity to obtain higher efficiency. For the terahertz emission, the QDs embedded in coupled double-cavity structures with an AlAs/GaAs intermediate distributed Bragg reflector (DBR) are grown on GaAs substrates. Two emission peaks at 1180, 1206 nm from the QDs corresponding to the coupled double-cavity resonant modes are observed in the high reflection band. The frequency differences for the two resonant… Advisors/Committee Members: Lung-Han Peng (chair), Jian-Jang Huang (chair), Wood-Hi Cheng (chair), Sheng-Di Lin (chair), Yung-Jui Chen (chair), Keh-Yung Cheng (chair), Tsong-Sheng Lay (committee member), Ching-Hwa Ho (chair), Hao-Hsiung Lin (chair).

Subjects/Keywords: laser; super luminescence diode; solar cell; broadband; molecular beam epitaxy; quantum dot

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Tzeng, T. (2011). InGaAs Quantum Dots grown by Molecular Beam Epitaxy. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0907111-100334

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Tzeng, Te-En. “InGaAs Quantum Dots grown by Molecular Beam Epitaxy.” 2011. Thesis, NSYSU. Accessed April 06, 2020. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0907111-100334.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Tzeng, Te-En. “InGaAs Quantum Dots grown by Molecular Beam Epitaxy.” 2011. Web. 06 Apr 2020.

Vancouver:

Tzeng T. InGaAs Quantum Dots grown by Molecular Beam Epitaxy. [Internet] [Thesis]. NSYSU; 2011. [cited 2020 Apr 06]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0907111-100334.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tzeng T. InGaAs Quantum Dots grown by Molecular Beam Epitaxy. [Thesis]. NSYSU; 2011. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0907111-100334

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.