Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study ai... more Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study aimed to define efficient and safe tissue-selective targeted gene therapy approaches for delivering genes into keratocytes of the cornea in vivo using a normal or diseased rabbit model. New Zealand White rabbits, adeno-associated virus serotype 5 (AAV5), and a minimally invasive hair-dryer based vector-delivery technique were used. Fifty microliters of AAV5 titer (6.5610 12 vg/ml) expressing green fluorescent protein gene (GFP) was topically applied onto normal or diseased (fibrotic or neovascularized) rabbit corneas for 2-minutes with a custom vector-delivery technique. Corneal fibrosis and neovascularization in rabbit eyes were induced with photorefractive keratectomy using excimer laser and VEGF (630 ng) using micropocket assay, respectively. Slitlamp biomicroscopy and immunocytochemistry were used to confirm fibrosis and neovascularization in rabbit corneas. The levels, location and duration of delivered-GFP gene expression in the rabbit stroma were measured with immunocytochemistry and/or western blotting. Slot-blot measured delivered-GFP gene copy number. Confocal microscopy performed in whole-mounts of cornea and thick corneal sections determined geometric and spatial localization of delivered-GFP in three-dimensional arrangement. AAV5 toxicity and safety were evaluated with clinical eye exam, stereomicroscopy, slit-lamp biomicroscopy, and H&E staining. A single 2-minute AAV5 topical application via custom delivery-technique efficiently and selectively transduced keratocytes in the anterior stroma of normal and diseased rabbit corneas as evident from immunocytochemistry and confocal microscopy. Transgene expression was first detected at day 3, peaked at day 7, and was maintained up to 16 weeks (longest tested time point). Clinical and slit-lamp eye examination in live rabbits and H&E staining did not reveal any significant changes between AAV5-treated and untreated control corneas. These findings suggest that defined gene therapy approaches are safe for delivering genes into keratocytes in vivo and has potential for treating corneal disorders in human patients.
Nanomedicine-nanotechnology Biology and Medicine, 2011
This study examined the gene transfer efficiency and toxicity of 2-kDa polyethylenimine conjugate... more This study examined the gene transfer efficiency and toxicity of 2-kDa polyethylenimine conjugated to gold nanoparticles (PEI2-GNP) in the human cornea in vitro and rabbit cornea in vivo. PEI2-GNP with nitrogen-to-phosphorus (N/P) ratios of up to 180 exhibited significant transgene delivery in the human cornea without altering the viability or phenotype of these cells. Similarly, PEI2-GNP applied to corneal tissues collected after 12 h, 72 h, or 7 days exhibited appreciable gold uptake throughout the rabbit stroma with gradual clearance of GNP over time. Transmission electron microscopy detected GNP in the keratocytes and the extracellular matrix of the rabbit corneas. Additionally, slitlamp biomicroscopy in live animals even 7 days after topical PEI2-GNP application to the cornea detected no inflammation, redness, or edema in rabbit eyes in vivo, with only moderate cell death and immune reactions. These results suggest that PEI2-GNP are safe for the cornea and can be potentially useful for corneal gene therapy in vivo.
Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular ti... more Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular tissues. This study tested a hypothesis that tissue-selective targeted decorin gene therapy delivered to the rabbit stroma with adeno-associated virus serotype 5 (AAV5) impedes corneal neovascularization (CNV) in vivo without significant side effects. An established rabbit CNV model was used. Targeted decorin gene therapy in the rabbit stroma was delivered with a single topical AAV5 titer (100 ml; 5610 12 vg/ml) application onto the stroma for two minutes after removing corneal epithelium. The levels of CNV were examined with stereomicroscopy, H&E staining, lectin, collagen type IV, CD31 immunocytochemistry and CD31 immunoblotting. Real-time PCR quantified mRNA expression of pro-and anti-angiogenic genes. Corneal health in live animals was monitored with clinical, slit-lamp and optical coherence tomography biomicroscopic examinations. Selective decorin delivery into stroma showed significant 52% (p,0.05), 66% (p,0.001), and 63% (p,0.01) reduction at early (day 5), mid (day 10), and late (day 14) stages of CNV in decorin-delivered rabbit corneas compared to control (no decorin delivered) corneas in morphometric analysis. The H&E staining, lectin, collagen type IV, CD31 immunostaining (57-65, p,0.5), and CD31 immunoblotting (62-67%, p,0.05) supported morphometric findings. Quantitative PCR studies demonstrated decorin gene therapy down-regulated expression of VEGF, MCP1 and angiopoietin (pro-angiogenic) and up-regulated PEDF (anti-angiogenic) genes. The clinical, biomicroscopy and transmission electron microscopy studies revealed that AAV5mediated decorin gene therapy is safe for the cornea. Tissue-targeted AAV5-mediated decorin gene therapy decreases CNV with no major side effects, and could potentially be used for treating patients.
Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study ai... more Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study aimed to define efficient and safe tissue-selective targeted gene therapy approaches for delivering genes into keratocytes of the cornea in vivo using a normal or diseased rabbit model. New Zealand White rabbits, adeno-associated virus serotype 5 (AAV5), and a minimally invasive hair-dryer based vector-delivery technique were used. Fifty microliters of AAV5 titer (6.5610 12 vg/ml) expressing green fluorescent protein gene (GFP) was topically applied onto normal or diseased (fibrotic or neovascularized) rabbit corneas for 2-minutes with a custom vector-delivery technique. Corneal fibrosis and neovascularization in rabbit eyes were induced with photorefractive keratectomy using excimer laser and VEGF (630 ng) using micropocket assay, respectively. Slitlamp biomicroscopy and immunocytochemistry were used to confirm fibrosis and neovascularization in rabbit corneas. The levels, location and duration of delivered-GFP gene expression in the rabbit stroma were measured with immunocytochemistry and/or western blotting. Slot-blot measured delivered-GFP gene copy number. Confocal microscopy performed in whole-mounts of cornea and thick corneal sections determined geometric and spatial localization of delivered-GFP in three-dimensional arrangement. AAV5 toxicity and safety were evaluated with clinical eye exam, stereomicroscopy, slit-lamp biomicroscopy, and H&E staining. A single 2-minute AAV5 topical application via custom delivery-technique efficiently and selectively transduced keratocytes in the anterior stroma of normal and diseased rabbit corneas as evident from immunocytochemistry and confocal microscopy. Transgene expression was first detected at day 3, peaked at day 7, and was maintained up to 16 weeks (longest tested time point). Clinical and slit-lamp eye examination in live rabbits and H&E staining did not reveal any significant changes between AAV5-treated and untreated control corneas. These findings suggest that defined gene therapy approaches are safe for delivering genes into keratocytes in vivo and has potential for treating corneal disorders in human patients.
Nanomedicine-nanotechnology Biology and Medicine, 2011
This study examined the gene transfer efficiency and toxicity of 2-kDa polyethylenimine conjugate... more This study examined the gene transfer efficiency and toxicity of 2-kDa polyethylenimine conjugated to gold nanoparticles (PEI2-GNP) in the human cornea in vitro and rabbit cornea in vivo. PEI2-GNP with nitrogen-to-phosphorus (N/P) ratios of up to 180 exhibited significant transgene delivery in the human cornea without altering the viability or phenotype of these cells. Similarly, PEI2-GNP applied to corneal tissues collected after 12 h, 72 h, or 7 days exhibited appreciable gold uptake throughout the rabbit stroma with gradual clearance of GNP over time. Transmission electron microscopy detected GNP in the keratocytes and the extracellular matrix of the rabbit corneas. Additionally, slitlamp biomicroscopy in live animals even 7 days after topical PEI2-GNP application to the cornea detected no inflammation, redness, or edema in rabbit eyes in vivo, with only moderate cell death and immune reactions. These results suggest that PEI2-GNP are safe for the cornea and can be potentially useful for corneal gene therapy in vivo.
Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular ti... more Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular tissues. This study tested a hypothesis that tissue-selective targeted decorin gene therapy delivered to the rabbit stroma with adeno-associated virus serotype 5 (AAV5) impedes corneal neovascularization (CNV) in vivo without significant side effects. An established rabbit CNV model was used. Targeted decorin gene therapy in the rabbit stroma was delivered with a single topical AAV5 titer (100 ml; 5610 12 vg/ml) application onto the stroma for two minutes after removing corneal epithelium. The levels of CNV were examined with stereomicroscopy, H&E staining, lectin, collagen type IV, CD31 immunocytochemistry and CD31 immunoblotting. Real-time PCR quantified mRNA expression of pro-and anti-angiogenic genes. Corneal health in live animals was monitored with clinical, slit-lamp and optical coherence tomography biomicroscopic examinations. Selective decorin delivery into stroma showed significant 52% (p,0.05), 66% (p,0.001), and 63% (p,0.01) reduction at early (day 5), mid (day 10), and late (day 14) stages of CNV in decorin-delivered rabbit corneas compared to control (no decorin delivered) corneas in morphometric analysis. The H&E staining, lectin, collagen type IV, CD31 immunostaining (57-65, p,0.5), and CD31 immunoblotting (62-67%, p,0.05) supported morphometric findings. Quantitative PCR studies demonstrated decorin gene therapy down-regulated expression of VEGF, MCP1 and angiopoietin (pro-angiogenic) and up-regulated PEDF (anti-angiogenic) genes. The clinical, biomicroscopy and transmission electron microscopy studies revealed that AAV5mediated decorin gene therapy is safe for the cornea. Tissue-targeted AAV5-mediated decorin gene therapy decreases CNV with no major side effects, and could potentially be used for treating patients.
We describe the growth and characteristics of AlInGaAs, self-aligned buried heterostructure quant... more We describe the growth and characteristics of AlInGaAs, self-aligned buried heterostructure quantum well lasers deposited by micro-selective-area growth. The lateral waveguide is defined by metalorganic vapor-phase epitaxy in narrow stripe openings; and the natural tendency to form smooth, no-growth {111} sidewall planes produces a low-loss, single-mode waveguide. By proper adjustment of the growth conditions after the waveguide formation, the waveguide may be buried in p-type InP. A buried heterostructure (BH) laser is there formed in a single growth step, eliminating the deterioration associated with air exposure and etch damage, especially for AlInGaAs active regions. The AlInGaAs BH lasers formed in this simple manner exhibit good performance characteristics, with room-temperature threshold current of 4mA.
In this letter, we demonstrate error-free operation of a 12-fiber 4-wavelength 5.21-Gb/s parallel... more In this letter, we demonstrate error-free operation of a 12-fiber 4-wavelength 5.21-Gb/s parallel-wavelength-division-multiplexed (PWDM) optical link. The 250-Gb/s transmitter and receiver assemblies each have a 5 8-mm footprint and consume a combined power of 1.5 W. To our knowledge, this is the first publication of a fully functional PWDM optical interconnect as well as the highest demonstrated bandwidth per unit area and bandwidth per unit power consumption for any multiple-channel fiber-optic interconnect. This technology is intended for short-distance high-bandwidth-density applications such as multiprocessor computer backplanes.
A parallel-optical interconnect with 12 channels operating at 8.5 Gb/s giving an aggregate data r... more A parallel-optical interconnect with 12 channels operating at 8.5 Gb/s giving an aggregate data rate of 102 Gb/s is demonstrated, to the authors' knowledge, for the first time. The paper describes and demonstrates 13 16-mm cross-section 12-channel parallel-optic transmitter and receiver modules with each channel operating at a data rate of 8.5-10 Gb/s. This was achieved using bottom-emitting 990-nm vertical-cavity surface-emitting lasers and bottom-illuminated InGaAs-InP photodetectors flip-chip bonded directly to 12-channel transmitter and receiver integrated circuits, respectively. In addition, 102-Gb/s link results are demonstrated over 100 m of 50-m-core standard multimode ribbon fiber. A bit-error ratio of 10 13 was measured on a single channel after transmission through 100 m of multimode fiber at a data rate of 8.5 Gb/s with all 12 channels operating simultaneously.
Abstract We proposed and demonstrated an Al gettering process for high-quality InGaAsN quantum we... more Abstract We proposed and demonstrated an Al gettering process for high-quality InGaAsN quantum wells grown by metalorganic chemical vapor deposition. Ammonia flow prior to InGaAsN growth eliminates undesirable Al incorporation in the InGaAsN continuously ...
We report results for broad area edge emitting lasers having AlInGaAs active regions that exhibit... more We report results for broad area edge emitting lasers having AlInGaAs active regions that exhibit low thresholds, high T0 and T1 and high efficiencies. The lasers were grown on InP substrates using MOCVD. This paper analyzes the effects of doping, epilayer design, wavelength ...
Abstract We obtained high-quality InGaAsN quantum wells (QWs) by metalorganic chemical vapor depo... more Abstract We obtained high-quality InGaAsN quantum wells (QWs) by metalorganic chemical vapor deposition (MOCVD). Our InGaAsN QWs showed low threshold current densities and high-temperature characteristics (550 A/cm 2, 150 K at 1275 nm for 3QWs) in broad-area ...
High temperature CW operation of electrically pumped 1.3-1.55 μm MQW VCSELs using top and bottom ... more High temperature CW operation of electrically pumped 1.3-1.55 μm MQW VCSELs using top and bottom InP/air-gap DBRs with record low threshold current density is demonstrated.
We report on the realization of InGaAs/ InAlAs quantum-cascade lasers grown by metalorganic vapor... more We report on the realization of InGaAs/ InAlAs quantum-cascade lasers grown by metalorganic vapor phase epitaxy operating in continuous wave with low-threshold current densities at temperatures as high as 188 K. Threshold current densities of 950 A / cm 2 and output powers of 125 mW are measured at 80 K, while 3 mW of continuous output power are measured at 180 K, with a threshold of 2.5 kA/ cm 2 . In pulsed mode, peak output powers of more than 0.4 W were obtained at 80 K and of 160 mW at 300 K with thresholds of 700 A / cm 2 and 2.75 kA/ cm 2 , respectively.
Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study ai... more Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study aimed to define efficient and safe tissue-selective targeted gene therapy approaches for delivering genes into keratocytes of the cornea in vivo using a normal or diseased rabbit model. New Zealand White rabbits, adeno-associated virus serotype 5 (AAV5), and a minimally invasive hair-dryer based vector-delivery technique were used. Fifty microliters of AAV5 titer (6.5610 12 vg/ml) expressing green fluorescent protein gene (GFP) was topically applied onto normal or diseased (fibrotic or neovascularized) rabbit corneas for 2-minutes with a custom vector-delivery technique. Corneal fibrosis and neovascularization in rabbit eyes were induced with photorefractive keratectomy using excimer laser and VEGF (630 ng) using micropocket assay, respectively. Slitlamp biomicroscopy and immunocytochemistry were used to confirm fibrosis and neovascularization in rabbit corneas. The levels, location and duration of delivered-GFP gene expression in the rabbit stroma were measured with immunocytochemistry and/or western blotting. Slot-blot measured delivered-GFP gene copy number. Confocal microscopy performed in whole-mounts of cornea and thick corneal sections determined geometric and spatial localization of delivered-GFP in three-dimensional arrangement. AAV5 toxicity and safety were evaluated with clinical eye exam, stereomicroscopy, slit-lamp biomicroscopy, and H&E staining. A single 2-minute AAV5 topical application via custom delivery-technique efficiently and selectively transduced keratocytes in the anterior stroma of normal and diseased rabbit corneas as evident from immunocytochemistry and confocal microscopy. Transgene expression was first detected at day 3, peaked at day 7, and was maintained up to 16 weeks (longest tested time point). Clinical and slit-lamp eye examination in live rabbits and H&E staining did not reveal any significant changes between AAV5-treated and untreated control corneas. These findings suggest that defined gene therapy approaches are safe for delivering genes into keratocytes in vivo and has potential for treating corneal disorders in human patients.
Nanomedicine-nanotechnology Biology and Medicine, 2011
This study examined the gene transfer efficiency and toxicity of 2-kDa polyethylenimine conjugate... more This study examined the gene transfer efficiency and toxicity of 2-kDa polyethylenimine conjugated to gold nanoparticles (PEI2-GNP) in the human cornea in vitro and rabbit cornea in vivo. PEI2-GNP with nitrogen-to-phosphorus (N/P) ratios of up to 180 exhibited significant transgene delivery in the human cornea without altering the viability or phenotype of these cells. Similarly, PEI2-GNP applied to corneal tissues collected after 12 h, 72 h, or 7 days exhibited appreciable gold uptake throughout the rabbit stroma with gradual clearance of GNP over time. Transmission electron microscopy detected GNP in the keratocytes and the extracellular matrix of the rabbit corneas. Additionally, slitlamp biomicroscopy in live animals even 7 days after topical PEI2-GNP application to the cornea detected no inflammation, redness, or edema in rabbit eyes in vivo, with only moderate cell death and immune reactions. These results suggest that PEI2-GNP are safe for the cornea and can be potentially useful for corneal gene therapy in vivo.
Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular ti... more Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular tissues. This study tested a hypothesis that tissue-selective targeted decorin gene therapy delivered to the rabbit stroma with adeno-associated virus serotype 5 (AAV5) impedes corneal neovascularization (CNV) in vivo without significant side effects. An established rabbit CNV model was used. Targeted decorin gene therapy in the rabbit stroma was delivered with a single topical AAV5 titer (100 ml; 5610 12 vg/ml) application onto the stroma for two minutes after removing corneal epithelium. The levels of CNV were examined with stereomicroscopy, H&E staining, lectin, collagen type IV, CD31 immunocytochemistry and CD31 immunoblotting. Real-time PCR quantified mRNA expression of pro-and anti-angiogenic genes. Corneal health in live animals was monitored with clinical, slit-lamp and optical coherence tomography biomicroscopic examinations. Selective decorin delivery into stroma showed significant 52% (p,0.05), 66% (p,0.001), and 63% (p,0.01) reduction at early (day 5), mid (day 10), and late (day 14) stages of CNV in decorin-delivered rabbit corneas compared to control (no decorin delivered) corneas in morphometric analysis. The H&E staining, lectin, collagen type IV, CD31 immunostaining (57-65, p,0.5), and CD31 immunoblotting (62-67%, p,0.05) supported morphometric findings. Quantitative PCR studies demonstrated decorin gene therapy down-regulated expression of VEGF, MCP1 and angiopoietin (pro-angiogenic) and up-regulated PEDF (anti-angiogenic) genes. The clinical, biomicroscopy and transmission electron microscopy studies revealed that AAV5mediated decorin gene therapy is safe for the cornea. Tissue-targeted AAV5-mediated decorin gene therapy decreases CNV with no major side effects, and could potentially be used for treating patients.
Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study ai... more Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study aimed to define efficient and safe tissue-selective targeted gene therapy approaches for delivering genes into keratocytes of the cornea in vivo using a normal or diseased rabbit model. New Zealand White rabbits, adeno-associated virus serotype 5 (AAV5), and a minimally invasive hair-dryer based vector-delivery technique were used. Fifty microliters of AAV5 titer (6.5610 12 vg/ml) expressing green fluorescent protein gene (GFP) was topically applied onto normal or diseased (fibrotic or neovascularized) rabbit corneas for 2-minutes with a custom vector-delivery technique. Corneal fibrosis and neovascularization in rabbit eyes were induced with photorefractive keratectomy using excimer laser and VEGF (630 ng) using micropocket assay, respectively. Slitlamp biomicroscopy and immunocytochemistry were used to confirm fibrosis and neovascularization in rabbit corneas. The levels, location and duration of delivered-GFP gene expression in the rabbit stroma were measured with immunocytochemistry and/or western blotting. Slot-blot measured delivered-GFP gene copy number. Confocal microscopy performed in whole-mounts of cornea and thick corneal sections determined geometric and spatial localization of delivered-GFP in three-dimensional arrangement. AAV5 toxicity and safety were evaluated with clinical eye exam, stereomicroscopy, slit-lamp biomicroscopy, and H&E staining. A single 2-minute AAV5 topical application via custom delivery-technique efficiently and selectively transduced keratocytes in the anterior stroma of normal and diseased rabbit corneas as evident from immunocytochemistry and confocal microscopy. Transgene expression was first detected at day 3, peaked at day 7, and was maintained up to 16 weeks (longest tested time point). Clinical and slit-lamp eye examination in live rabbits and H&E staining did not reveal any significant changes between AAV5-treated and untreated control corneas. These findings suggest that defined gene therapy approaches are safe for delivering genes into keratocytes in vivo and has potential for treating corneal disorders in human patients.
Nanomedicine-nanotechnology Biology and Medicine, 2011
This study examined the gene transfer efficiency and toxicity of 2-kDa polyethylenimine conjugate... more This study examined the gene transfer efficiency and toxicity of 2-kDa polyethylenimine conjugated to gold nanoparticles (PEI2-GNP) in the human cornea in vitro and rabbit cornea in vivo. PEI2-GNP with nitrogen-to-phosphorus (N/P) ratios of up to 180 exhibited significant transgene delivery in the human cornea without altering the viability or phenotype of these cells. Similarly, PEI2-GNP applied to corneal tissues collected after 12 h, 72 h, or 7 days exhibited appreciable gold uptake throughout the rabbit stroma with gradual clearance of GNP over time. Transmission electron microscopy detected GNP in the keratocytes and the extracellular matrix of the rabbit corneas. Additionally, slitlamp biomicroscopy in live animals even 7 days after topical PEI2-GNP application to the cornea detected no inflammation, redness, or edema in rabbit eyes in vivo, with only moderate cell death and immune reactions. These results suggest that PEI2-GNP are safe for the cornea and can be potentially useful for corneal gene therapy in vivo.
Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular ti... more Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular tissues. This study tested a hypothesis that tissue-selective targeted decorin gene therapy delivered to the rabbit stroma with adeno-associated virus serotype 5 (AAV5) impedes corneal neovascularization (CNV) in vivo without significant side effects. An established rabbit CNV model was used. Targeted decorin gene therapy in the rabbit stroma was delivered with a single topical AAV5 titer (100 ml; 5610 12 vg/ml) application onto the stroma for two minutes after removing corneal epithelium. The levels of CNV were examined with stereomicroscopy, H&E staining, lectin, collagen type IV, CD31 immunocytochemistry and CD31 immunoblotting. Real-time PCR quantified mRNA expression of pro-and anti-angiogenic genes. Corneal health in live animals was monitored with clinical, slit-lamp and optical coherence tomography biomicroscopic examinations. Selective decorin delivery into stroma showed significant 52% (p,0.05), 66% (p,0.001), and 63% (p,0.01) reduction at early (day 5), mid (day 10), and late (day 14) stages of CNV in decorin-delivered rabbit corneas compared to control (no decorin delivered) corneas in morphometric analysis. The H&E staining, lectin, collagen type IV, CD31 immunostaining (57-65, p,0.5), and CD31 immunoblotting (62-67%, p,0.05) supported morphometric findings. Quantitative PCR studies demonstrated decorin gene therapy down-regulated expression of VEGF, MCP1 and angiopoietin (pro-angiogenic) and up-regulated PEDF (anti-angiogenic) genes. The clinical, biomicroscopy and transmission electron microscopy studies revealed that AAV5mediated decorin gene therapy is safe for the cornea. Tissue-targeted AAV5-mediated decorin gene therapy decreases CNV with no major side effects, and could potentially be used for treating patients.
We describe the growth and characteristics of AlInGaAs, self-aligned buried heterostructure quant... more We describe the growth and characteristics of AlInGaAs, self-aligned buried heterostructure quantum well lasers deposited by micro-selective-area growth. The lateral waveguide is defined by metalorganic vapor-phase epitaxy in narrow stripe openings; and the natural tendency to form smooth, no-growth {111} sidewall planes produces a low-loss, single-mode waveguide. By proper adjustment of the growth conditions after the waveguide formation, the waveguide may be buried in p-type InP. A buried heterostructure (BH) laser is there formed in a single growth step, eliminating the deterioration associated with air exposure and etch damage, especially for AlInGaAs active regions. The AlInGaAs BH lasers formed in this simple manner exhibit good performance characteristics, with room-temperature threshold current of 4mA.
In this letter, we demonstrate error-free operation of a 12-fiber 4-wavelength 5.21-Gb/s parallel... more In this letter, we demonstrate error-free operation of a 12-fiber 4-wavelength 5.21-Gb/s parallel-wavelength-division-multiplexed (PWDM) optical link. The 250-Gb/s transmitter and receiver assemblies each have a 5 8-mm footprint and consume a combined power of 1.5 W. To our knowledge, this is the first publication of a fully functional PWDM optical interconnect as well as the highest demonstrated bandwidth per unit area and bandwidth per unit power consumption for any multiple-channel fiber-optic interconnect. This technology is intended for short-distance high-bandwidth-density applications such as multiprocessor computer backplanes.
A parallel-optical interconnect with 12 channels operating at 8.5 Gb/s giving an aggregate data r... more A parallel-optical interconnect with 12 channels operating at 8.5 Gb/s giving an aggregate data rate of 102 Gb/s is demonstrated, to the authors' knowledge, for the first time. The paper describes and demonstrates 13 16-mm cross-section 12-channel parallel-optic transmitter and receiver modules with each channel operating at a data rate of 8.5-10 Gb/s. This was achieved using bottom-emitting 990-nm vertical-cavity surface-emitting lasers and bottom-illuminated InGaAs-InP photodetectors flip-chip bonded directly to 12-channel transmitter and receiver integrated circuits, respectively. In addition, 102-Gb/s link results are demonstrated over 100 m of 50-m-core standard multimode ribbon fiber. A bit-error ratio of 10 13 was measured on a single channel after transmission through 100 m of multimode fiber at a data rate of 8.5 Gb/s with all 12 channels operating simultaneously.
Abstract We proposed and demonstrated an Al gettering process for high-quality InGaAsN quantum we... more Abstract We proposed and demonstrated an Al gettering process for high-quality InGaAsN quantum wells grown by metalorganic chemical vapor deposition. Ammonia flow prior to InGaAsN growth eliminates undesirable Al incorporation in the InGaAsN continuously ...
We report results for broad area edge emitting lasers having AlInGaAs active regions that exhibit... more We report results for broad area edge emitting lasers having AlInGaAs active regions that exhibit low thresholds, high T0 and T1 and high efficiencies. The lasers were grown on InP substrates using MOCVD. This paper analyzes the effects of doping, epilayer design, wavelength ...
Abstract We obtained high-quality InGaAsN quantum wells (QWs) by metalorganic chemical vapor depo... more Abstract We obtained high-quality InGaAsN quantum wells (QWs) by metalorganic chemical vapor deposition (MOCVD). Our InGaAsN QWs showed low threshold current densities and high-temperature characteristics (550 A/cm 2, 150 K at 1275 nm for 3QWs) in broad-area ...
High temperature CW operation of electrically pumped 1.3-1.55 μm MQW VCSELs using top and bottom ... more High temperature CW operation of electrically pumped 1.3-1.55 μm MQW VCSELs using top and bottom InP/air-gap DBRs with record low threshold current density is demonstrated.
We report on the realization of InGaAs/ InAlAs quantum-cascade lasers grown by metalorganic vapor... more We report on the realization of InGaAs/ InAlAs quantum-cascade lasers grown by metalorganic vapor phase epitaxy operating in continuous wave with low-threshold current densities at temperatures as high as 188 K. Threshold current densities of 950 A / cm 2 and output powers of 125 mW are measured at 80 K, while 3 mW of continuous output power are measured at 180 K, with a threshold of 2.5 kA/ cm 2 . In pulsed mode, peak output powers of more than 0.4 W were obtained at 80 K and of 160 mW at 300 K with thresholds of 700 A / cm 2 and 2.75 kA/ cm 2 , respectively.
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Papers by Ashish Tandon