There has been increasing interest in optical computing for ultrafast information processing. To realize optical computing systems, there are several key devices, such as surface-emitting lasers and optical switching devices.
{"title":"Applications of Quantum Well Structures for Surface Emitting Lasers and Optical Switching Devices","authors":"K. Kyuma, K. Kojima, T. Nakayama","doi":"10.1364/qwoe.1989.tuc1","DOIUrl":"https://doi.org/10.1364/qwoe.1989.tuc1","url":null,"abstract":"There has been increasing interest in optical computing for ultrafast information processing. To realize optical computing systems, there are several key devices, such as surface-emitting lasers and optical switching devices.","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132096630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Diamond, E. Özbay, M. Rodwell, D. Bloom, Y. Pao, E. Wolak, J. S. Harris
For digital circuit applications such as binary and multi-level logic circuits, device isolation is required to integrate several devices on chip. Microwave circuit applications such as mixers, and frequency multipliers require a low loss nonconducting substrate for on-chip integrations of high quality transmission lines and other passive microwave structures. We have demonstrated a fabrication process which produces high quality RTD’s with a maximum frequency of oscillation above 200 GHz in a process suitable for switching applications, integrations of devices and microwave structures
{"title":"Fabrication of Resonant Tunneling Diodes for Switching Applications","authors":"S. Diamond, E. Özbay, M. Rodwell, D. Bloom, Y. Pao, E. Wolak, J. S. Harris","doi":"10.1364/qwoe.1989.wc4","DOIUrl":"https://doi.org/10.1364/qwoe.1989.wc4","url":null,"abstract":"For digital circuit applications such as binary and multi-level logic circuits, device isolation is required to integrate several devices on chip. Microwave circuit applications such as mixers, and frequency multipliers require a low loss nonconducting substrate for on-chip integrations of high quality transmission lines and other passive microwave structures. We have demonstrated a fabrication process which produces high quality RTD’s with a maximum frequency of oscillation above 200 GHz in a process suitable for switching applications, integrations of devices and microwave structures","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127854423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Hsu, W. Y. Wu, U. Efron, J. Schulman, G. Hasnain
A GaAs Nipi with selective contacts was used for refractive modulation characterization; this Nipi device has the alternative n- and p-doped thin layers at a total thickness of ≅ 0.68 μm and a doping concentration of n ≅ p ≅ 4×1018 cm-3. The selective contactings were grown in situ with the n-i-p-i structure by MBE technology. The distance between two contact electrodes is ≅ 0.7 mm and each electrode is measured at ≅ 1 mm in length. The active area of this device is, therefore, approximately 0.7 mm × 1 mm. The I-V measurement of this n-i-p-i device shows good diode characteristics. The refractive changes at various current levels were determined by using a Mach-Zehnder interferometer. An Ar+-laser pumped ring dye laser, which has a useful wavelength range from 8000 to 9000 Å, was used as a light source. The refractive index change was determined by the fringe shift of the interference pattern generated by the signal beam (which passes through the n-i-p-i device) and the reference beam. A train of current pulses at a few hertz was used to drive the n-i-p-i modulator and also eliminate the slow fringe drift due to environmental noises of the interferometric system. A positive refractive index change of Δn > 1.5 was recorded at an injection current level I < 50 mA at λ = 9000 Å, as shown in Figure 1. The above result of refractive index modulation is more than two orders of magnitude larger than the prediction from our theoretical calculation.1 This refractive index change is observed in the wavelength range from 8900 Å to 9050 Å. The measurement wavelength range was limited by the strong interband absorption at λ < 8900 Å, and by the cutoff lasing wavelength of the sty-9 dye used in our ring dye laser beyond λ > 9050 Å.
{"title":"Refractive Index Modulation in Selectively Contacted GaAs N-I-P-I Structures","authors":"T. Hsu, W. Y. Wu, U. Efron, J. Schulman, G. Hasnain","doi":"10.1364/qwoe.1989.tue14","DOIUrl":"https://doi.org/10.1364/qwoe.1989.tue14","url":null,"abstract":"A GaAs Nipi with selective contacts was used for refractive modulation characterization; this Nipi device has the alternative n- and p-doped thin layers at a total thickness of ≅ 0.68 μm and a doping concentration of n ≅ p ≅ 4×1018 cm-3. The selective contactings were grown in situ with the n-i-p-i structure by MBE technology. The distance between two contact electrodes is ≅ 0.7 mm and each electrode is measured at ≅ 1 mm in length. The active area of this device is, therefore, approximately 0.7 mm × 1 mm. The I-V measurement of this n-i-p-i device shows good diode characteristics. The refractive changes at various current levels were determined by using a Mach-Zehnder interferometer. An Ar+-laser pumped ring dye laser, which has a useful wavelength range from 8000 to 9000 Å, was used as a light source. The refractive index change was determined by the fringe shift of the interference pattern generated by the signal beam (which passes through the n-i-p-i device) and the reference beam. A train of current pulses at a few hertz was used to drive the n-i-p-i modulator and also eliminate the slow fringe drift due to environmental noises of the interferometric system. A positive refractive index change of Δn > 1.5 was recorded at an injection current level I < 50 mA at λ = 9000 Å, as shown in Figure 1. The above result of refractive index modulation is more than two orders of magnitude larger than the prediction from our theoretical calculation.1 This refractive index change is observed in the wavelength range from 8900 Å to 9050 Å. The measurement wavelength range was limited by the strong interband absorption at λ < 8900 Å, and by the cutoff lasing wavelength of the sty-9 dye used in our ring dye laser beyond λ > 9050 Å.","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"212 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114572575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Korn, A. Forchel, R. Germann, K. Streubel, U. Cebulla
We have fabricated 1st order phase shifted DFB-gratings for the 1.5 µm wavelength range on MOCVD grown InGaAs/InP-multi quantum well (MQW) layers. The dynamic properties were investigated by a new optical method which allows to test the high frequency behaviour of the devices far into the GHz range.
{"title":"Fabrication and Optical High Speed Characterization of Phase-Shifted InGaAs/InP Multi Quantum Well DFB Structures","authors":"M. Korn, A. Forchel, R. Germann, K. Streubel, U. Cebulla","doi":"10.1364/qwoe.1989.tub3","DOIUrl":"https://doi.org/10.1364/qwoe.1989.tub3","url":null,"abstract":"We have fabricated 1st order phase shifted DFB-gratings for the 1.5 µm wavelength range on MOCVD grown InGaAs/InP-multi quantum well (MQW) layers. The dynamic properties were investigated by a new optical method which allows to test the high frequency behaviour of the devices far into the GHz range.","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121152873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Multiple quantum well (MQW) semiconductors provide a number of nonlinear optical effects associated with well resolved, room temperature, exciton absorption features. Refractive nonlinearities arising from the saturation of the exciton by phase space filling, and the electric field induced quantum confined Stark effect (QCSE) can both be used to produce nonlinear characteristics at low laser powers. We use these effects to monitor optically created excess carrier dynamics in GaAs/AlGaAs MQW structures at room temperature on picosecond timescales. In particular, we have determined the time constants relating to cross-well carrier diffusion by thermionic emission from quantum wells, and tunnelling through 60Å barriers in the presence of an electrical field. Measurement of the temperature dependence of four wave mixing decay rates allows a study of the thermionic emission process, while the voltage dependence of the build up time of the crosswell photocurrent establishes the latter. The differential emission rates for both processes will be discussed.
{"title":"Optical Nonlinearities and Cross-Well Transport In Multiple Quantum Well Structures","authors":"A. Miller, R. Manning, P. J. Bradley","doi":"10.1364/qwoe.1989.mc1","DOIUrl":"https://doi.org/10.1364/qwoe.1989.mc1","url":null,"abstract":"Multiple quantum well (MQW) semiconductors provide a number of nonlinear optical effects associated with well resolved, room temperature, exciton absorption features. Refractive nonlinearities arising from the saturation of the exciton by phase space filling, and the electric field induced quantum confined Stark effect (QCSE) can both be used to produce nonlinear characteristics at low laser powers. We use these effects to monitor optically created excess carrier dynamics in GaAs/AlGaAs MQW structures at room temperature on picosecond timescales. In particular, we have determined the time constants relating to cross-well carrier diffusion by thermionic emission from quantum wells, and tunnelling through 60Å barriers in the presence of an electrical field. Measurement of the temperature dependence of four wave mixing decay rates allows a study of the thermionic emission process, while the voltage dependence of the build up time of the crosswell photocurrent establishes the latter. The differential emission rates for both processes will be discussed.","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122781894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pseudomorphic InGaAs quantum well (QW) structures have been the subject of considerable interest for electronic and optoelectronic devices. In order to optimize pseudomorphic QW structures for advanced devices it is necessary to understand the properties of the interfaces with the barrier layers. To this end we have utilized photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopy to investigate the optical properties of InGaAs strained single quantum wells (QWs) grown by molecular beam epitaxy with different barrier layers. Samples with 100A In.15Ga.85As layers bounded on top and bottom by either GaAs or Al.15Ga.85As were studied over the temperature range 2-300 K. All four possible barrier combinations were included. The GaAs/InGaAs/GaAs samples exhibited linewidths as small as 1.3 meV at 2 K, which are the narrowest yet observed for these structures grown by conventional techniques. Similar results were observed at 2 K for QWs with AlGaAs barriers below, but the linewidths of samples with AlGaAs on top were substantially broadened. Measurements of the excitation spectra of these samples showed a substantial free exciton component to the luminescence from samples without top AlGaAs barriers. Samples with top AlGaAs barriers, however, showed little free exciton contribution. Investigation of the temperature behavior of the luminescence suggest that the homogeneous broadening in all the samples is similar, but that the inhomogeneous contributions are different for the various structures. In addition, the temperature dependent measurements showed an additional bound exciton component of the samples with top barriers that was ionized at temperatures above 15 K. Samples with lower AlGaAs barriers showed an anomalous increase in linewidth with increasing temperature which is still under investigation.
{"title":"Excitonic Behavior in Pseudomorphic InGaAs/(Al)GaAs Quantum Wells Grown by Mbe","authors":"D. Ackley, C. Colvard, H. Lee, N. Nouri","doi":"10.1364/qwoe.1989.tue5","DOIUrl":"https://doi.org/10.1364/qwoe.1989.tue5","url":null,"abstract":"Pseudomorphic InGaAs quantum well (QW) structures have been the subject of considerable interest for electronic and optoelectronic devices. In order to optimize pseudomorphic QW structures for advanced devices it is necessary to understand the properties of the interfaces with the barrier layers. To this end we have utilized photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopy to investigate the optical properties of InGaAs strained single quantum wells (QWs) grown by molecular beam epitaxy with different barrier layers. Samples with 100A In.15Ga.85As layers bounded on top and bottom by either GaAs or Al.15Ga.85As were studied over the temperature range 2-300 K. All four possible barrier combinations were included. The GaAs/InGaAs/GaAs samples exhibited linewidths as small as 1.3 meV at 2 K, which are the narrowest yet observed for these structures grown by conventional techniques. Similar results were observed at 2 K for QWs with AlGaAs barriers below, but the linewidths of samples with AlGaAs on top were substantially broadened. Measurements of the excitation spectra of these samples showed a substantial free exciton component to the luminescence from samples without top AlGaAs barriers. Samples with top AlGaAs barriers, however, showed little free exciton contribution. Investigation of the temperature behavior of the luminescence suggest that the homogeneous broadening in all the samples is similar, but that the inhomogeneous contributions are different for the various structures. In addition, the temperature dependent measurements showed an additional bound exciton component of the samples with top barriers that was ionized at temperatures above 15 K. Samples with lower AlGaAs barriers showed an anomalous increase in linewidth with increasing temperature which is still under investigation.","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"238 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131587898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. E. VanEck, S. Niki, P. Chu, W. Chang, H. Wieder, A. Mardinly, K. Aron, G. Hansen
Good electroabsorption has been demonstrated recently in InGaAs/GaAs quantum wells.1,2 A structure described previously1 had only ten quantum wells, and although InGaAs and GaAs are not lattice-matched, the total strain energy in this structure was small enough that the quantum wells grew pseudomorphically, i. e., the InGaAs was strained so that its in-plane lattice constant was equal to the lattice constant of the GaAs substrate. This structure showed good electroabsorption characteristics, but only 6% modulation depth. For a device with 50% modulation depth, about 100 quantum wells are required. However, structures containing only 20 quantum wells appeared to be non-pseudomorphic. Thus 100 quantum wells can not be grown pseudomorphic to the substrate, yet they must be grown with no dislocations to have good electroabsorption characteristics. This can be accomplished by growing the quantum well structure on top of a thick, uniform buffer layer with a lattice constant equal to the weighted average of the lattice constants of the quantum well and buffer layers. Lattice relaxation by means of dislocations occurs only in the buffer layer, and both quantum wells and barriers grow pseudomorphic to the buffer layer rather than the substrate.3 A similar result can be achieved by eliminating the buffer layer; the lattice relaxation occurs in the first few quantum wells, and the rest are dislocation-free.2,4,5 We have employed this method to produce a structure with 80 quantum wells which exhibits good electroabsorption characteristics. We have also grown 50 quantum wells on a strained superlattice buffer layer consisting of alternating layers of InGaAs and GaAs, each 20Å thick. The purpose of this is to remove the dislocations from the quantum wells, which are optically active, and place them in the inactive superlattice.
{"title":"A Strained Superlattice Buffer Layer for InGaAs/GaAs Quantum Wells","authors":"T. E. VanEck, S. Niki, P. Chu, W. Chang, H. Wieder, A. Mardinly, K. Aron, G. Hansen","doi":"10.1364/qwoe.1989.wa3","DOIUrl":"https://doi.org/10.1364/qwoe.1989.wa3","url":null,"abstract":"Good electroabsorption has been demonstrated recently in InGaAs/GaAs quantum wells.1,2 A structure described previously1 had only ten quantum wells, and although InGaAs and GaAs are not lattice-matched, the total strain energy in this structure was small enough that the quantum wells grew pseudomorphically, i. e., the InGaAs was strained so that its in-plane lattice constant was equal to the lattice constant of the GaAs substrate. This structure showed good electroabsorption characteristics, but only 6% modulation depth. For a device with 50% modulation depth, about 100 quantum wells are required. However, structures containing only 20 quantum wells appeared to be non-pseudomorphic. Thus 100 quantum wells can not be grown pseudomorphic to the substrate, yet they must be grown with no dislocations to have good electroabsorption characteristics. This can be accomplished by growing the quantum well structure on top of a thick, uniform buffer layer with a lattice constant equal to the weighted average of the lattice constants of the quantum well and buffer layers. Lattice relaxation by means of dislocations occurs only in the buffer layer, and both quantum wells and barriers grow pseudomorphic to the buffer layer rather than the substrate.3 A similar result can be achieved by eliminating the buffer layer; the lattice relaxation occurs in the first few quantum wells, and the rest are dislocation-free.2,4,5 We have employed this method to produce a structure with 80 quantum wells which exhibits good electroabsorption characteristics. We have also grown 50 quantum wells on a strained superlattice buffer layer consisting of alternating layers of InGaAs and GaAs, each 20Å thick. The purpose of this is to remove the dislocations from the quantum wells, which are optically active, and place them in the inactive superlattice.","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130231996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In addition to quantum confinement [1], the effects of strain, resulting from the growth of lattice-mismatched materials, provide another means of tailoring the properties and performance of optoelectronic devices [2-6]. New properties for device applications, including birefringence and piezoelectric effects [7], are expected.
{"title":"Photoreflectance Spectroscopy of InGaAs/GaAs Strained Superlattice Waveguides","authors":"G. Sonek, L. Dawson","doi":"10.1364/qwoe.1989.tue3","DOIUrl":"https://doi.org/10.1364/qwoe.1989.tue3","url":null,"abstract":"In addition to quantum confinement [1], the effects of strain, resulting from the growth of lattice-mismatched materials, provide another means of tailoring the properties and performance of optoelectronic devices [2-6]. New properties for device applications, including birefringence and piezoelectric effects [7], are expected.","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127493624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Doughty, P. Holtz, R. Simes, A. Gossard, J. Maseijian, J. Merz
Infrared detectors (2-25 microns) have been a subject of much interest in recent years for defense and space exploration applications. Detectors built using II-VI compounds (for example, HgCdTe) have been investigated in depth, but suffer from the instability and nonuniformity of the materials, and from processing difficulties. Recently, quantum-well detectors using III-V compounds have been produced which demonstrate good detectivity in the 10 micron wavelength region 1,2. Their approach is based on inter-subband absorption in quantum-wells, or on confined-state to conduction-band transitions, and is limited to a fixed band of wavelengths for a given detector.
{"title":"Tunable Quantum-Well Infrared Detector","authors":"K. Doughty, P. Holtz, R. Simes, A. Gossard, J. Maseijian, J. Merz","doi":"10.1364/qwoe.1989.tue11","DOIUrl":"https://doi.org/10.1364/qwoe.1989.tue11","url":null,"abstract":"Infrared detectors (2-25 microns) have been a subject of much interest in recent years for defense and space exploration applications. Detectors built using II-VI compounds (for example, HgCdTe) have been investigated in depth, but suffer from the instability and nonuniformity of the materials, and from processing difficulties. Recently, quantum-well detectors using III-V compounds have been produced which demonstrate good detectivity in the 10 micron wavelength region 1,2. Their approach is based on inter-subband absorption in quantum-wells, or on confined-state to conduction-band transitions, and is limited to a fixed band of wavelengths for a given detector.","PeriodicalId":205579,"journal":{"name":"Quantum Wells for Optics and Optoelectronics","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115183973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：