Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.最新文献
Pub Date : 2004-09-27DOI: 10.1109/ICIMW.2004.1422234
I. de la Fuente, P. V. D. van der Slot, K. Boller
As part of the EC-funded MicroPro project, a table-top Cerenkov FEL is being realized that ultimately should generate 1 kW CW output power around 50 GHz. Design aspects and first experimental results are presented. The source is used for a number of applications.
{"title":"A table-top Cerenkov FEL at 50 GHz","authors":"I. de la Fuente, P. V. D. van der Slot, K. Boller","doi":"10.1109/ICIMW.2004.1422234","DOIUrl":"https://doi.org/10.1109/ICIMW.2004.1422234","url":null,"abstract":"As part of the EC-funded MicroPro project, a table-top Cerenkov FEL is being realized that ultimately should generate 1 kW CW output power around 50 GHz. Design aspects and first experimental results are presented. The source is used for a number of applications.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88905554","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}
Pub Date : 2004-09-14DOI: 10.1103/PHYSREVB.70.125205
F. Kadlec, H. Němec, P. Kužel
A novel scheme of optical pump-THz probe experiments was used to study the nonlinear absorption in GaAs. The crystal was excited by ultrashort laser pulses with wavelength 810 nm and fluences up to 4.2 mJ/cm/sup 2/, for which the single-photon absorption (SPA) saturates and the two-photon absorption (TPA) dominates. The TPA coefficient /spl beta/ and its anisotropy were determined.
{"title":"Optical two-photon absorption in GaAs measured by optical pump-terahertz probe spectroscopy","authors":"F. Kadlec, H. Němec, P. Kužel","doi":"10.1103/PHYSREVB.70.125205","DOIUrl":"https://doi.org/10.1103/PHYSREVB.70.125205","url":null,"abstract":"A novel scheme of optical pump-THz probe experiments was used to study the nonlinear absorption in GaAs. The crystal was excited by ultrashort laser pulses with wavelength 810 nm and fluences up to 4.2 mJ/cm/sup 2/, for which the single-photon absorption (SPA) saturates and the two-photon absorption (TPA) dominates. The TPA coefficient /spl beta/ and its anisotropy were determined.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79775657","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}
C. Middleton, G. Zummo, A. Weeks, A. Pergande, L. Mirth, G. Boreman
We built and tested a low-cost 8-by-8 millimeter-wave focal plane array using antenna-coupled micro-bolometers. The array consists of slot antennas coupled to nickel bolometers and was fabricated using optical lithography on high-resistivity silicon wafers. The measured noise equivalent temperature difference (NETD) of an individual element was 450 K. Simulation results corresponded with observed device performance. An improved design was then implemented using a square spiral antenna. We discuss the fabrication of this type of array element, including some modeling results, and present the methods and results of our measurements.
{"title":"Passive millimeter-wave focal plane array","authors":"C. Middleton, G. Zummo, A. Weeks, A. Pergande, L. Mirth, G. Boreman","doi":"10.1117/12.542753","DOIUrl":"https://doi.org/10.1117/12.542753","url":null,"abstract":"We built and tested a low-cost 8-by-8 millimeter-wave focal plane array using antenna-coupled micro-bolometers. The array consists of slot antennas coupled to nickel bolometers and was fabricated using optical lithography on high-resistivity silicon wafers. The measured noise equivalent temperature difference (NETD) of an individual element was 450 K. Simulation results corresponded with observed device performance. An improved design was then implemented using a square spiral antenna. We discuss the fabrication of this type of array element, including some modeling results, and present the methods and results of our measurements.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81103936","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}
Pub Date : 2004-07-25DOI: 10.1109/ICIMW.2004.1422108
G. Torosyan, C. Rau, B. Pradarutti, R. Beigang
Surface plasmon polaritons are excited in periodic metallic structures using fs THz pulses. The transmission and emission properties from a periodic structure of metallic rods with different diameters clearly show the influence of Wood's anomalies. The velocity of propagation of the surface plasmon polaritons is determined experimentally.
{"title":"Excitation and propagation of surface plasmon polaritons on metallic periodic structures","authors":"G. Torosyan, C. Rau, B. Pradarutti, R. Beigang","doi":"10.1109/ICIMW.2004.1422108","DOIUrl":"https://doi.org/10.1109/ICIMW.2004.1422108","url":null,"abstract":"Surface plasmon polaritons are excited in periodic metallic structures using fs THz pulses. The transmission and emission properties from a periodic structure of metallic rods with different diameters clearly show the influence of Wood's anomalies. The velocity of propagation of the surface plasmon polaritons is determined experimentally.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77944180","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}
Pub Date : 2004-07-01DOI: 10.1109/PLASMA.2004.1340112
F. Leuterer, G. Grunwald, F. Monaco, M. Munich, F. Ryter, H. Schutz, D. Wagner, H. Zohm, T. Franke, G. Dammertz, H. Heidinger, K. Koppenburg, M. Thumm, W. Kasparek, G. Gantenbein, G. Denisov, A. Litvak, V. Zapevalov
A multi-frequency ECRH system with 4 gyrotrons, tunable in the range of 105-140 GHz, is currently under construction at ASDEX Upgrade with a total power of 4 MW and a pulse length of 10 s. A fast steerable launcher for feedback controlled deposition has been installed that allows for poloidal steering of 10/spl deg/ within 100 ms. Transmission line elements, such as corrugated waveguides, polarizer mirrors and vacuum windows, are designed to cope for this frequency band.
{"title":"Progress in the new ECRH system for ASDEX Upgrade","authors":"F. Leuterer, G. Grunwald, F. Monaco, M. Munich, F. Ryter, H. Schutz, D. Wagner, H. Zohm, T. Franke, G. Dammertz, H. Heidinger, K. Koppenburg, M. Thumm, W. Kasparek, G. Gantenbein, G. Denisov, A. Litvak, V. Zapevalov","doi":"10.1109/PLASMA.2004.1340112","DOIUrl":"https://doi.org/10.1109/PLASMA.2004.1340112","url":null,"abstract":"A multi-frequency ECRH system with 4 gyrotrons, tunable in the range of 105-140 GHz, is currently under construction at ASDEX Upgrade with a total power of 4 MW and a pulse length of 10 s. A fast steerable launcher for feedback controlled deposition has been installed that allows for poloidal steering of 10/spl deg/ within 100 ms. Transmission line elements, such as corrugated waveguides, polarizer mirrors and vacuum windows, are designed to cope for this frequency band.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78987952","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}
Pub Date : 2004-07-01DOI: 10.1109/ICIMW.2004.1422184
R. Kaindl, D. Hägele, M. Carnahan, R. Lovenich, D. Chemla
We employ ultrafast terahertz (THz) pulses to study the dynamical interplay of optically-induced excitons and unbound electron-hole pairs in GaAs/AlGaAs quantum wells. A distinct low-energy oscillator appears upon resonant excitation of heavy-hole excitons, linked to transitions between their internal degrees of freedom. Time-resolving changes in the THz conductivity, we can observe dynamical transitions between conducting and insulating phases as excitons form or ionize on ultrashort timescales.
{"title":"Terahertz probes of transient conducting and insulating phases in quasi-2D electron-hole gases","authors":"R. Kaindl, D. Hägele, M. Carnahan, R. Lovenich, D. Chemla","doi":"10.1109/ICIMW.2004.1422184","DOIUrl":"https://doi.org/10.1109/ICIMW.2004.1422184","url":null,"abstract":"We employ ultrafast terahertz (THz) pulses to study the dynamical interplay of optically-induced excitons and unbound electron-hole pairs in GaAs/AlGaAs quantum wells. A distinct low-energy oscillator appears upon resonant excitation of heavy-hole excitons, linked to transitions between their internal degrees of freedom. Time-resolving changes in the THz conductivity, we can observe dynamical transitions between conducting and insulating phases as excitons form or ionize on ultrashort timescales.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90200718","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}
Pub Date : 2004-07-01DOI: 10.1109/ICIMW.2004.1422252
S. Chen, C. Chiu, T. Chang, K. Pao, K. Chu
The gyrotron backward-wave oscillator (gyro-BWO) is sensitive to external reflections because it employs a non-resonant interaction structure. These reflections may result in serious output power variations and ragged frequency tuning. A numerical model is developed for the investigation of the reflection effects. It treats beam-wave interactions in the presence of external reflections. As a hybrid feature of the formalism, external reflections are self-consistently determined by the structures, rather than artificially set as a constant value as in previous models. The model has been employed to examine the effects of external reflections on the tunable bandwidth of the gyro-BWO, and showed the resonance in the external circuit is the major cause of the ragged frequency tuning.
{"title":"Effects of external reflections on gyrotron backward wave oscillators","authors":"S. Chen, C. Chiu, T. Chang, K. Pao, K. Chu","doi":"10.1109/ICIMW.2004.1422252","DOIUrl":"https://doi.org/10.1109/ICIMW.2004.1422252","url":null,"abstract":"The gyrotron backward-wave oscillator (gyro-BWO) is sensitive to external reflections because it employs a non-resonant interaction structure. These reflections may result in serious output power variations and ragged frequency tuning. A numerical model is developed for the investigation of the reflection effects. It treats beam-wave interactions in the presence of external reflections. As a hybrid feature of the formalism, external reflections are self-consistently determined by the structures, rather than artificially set as a constant value as in previous models. The model has been employed to examine the effects of external reflections on the tunable bandwidth of the gyro-BWO, and showed the resonance in the external circuit is the major cause of the ragged frequency tuning.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87559175","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}
Pub Date : 2004-01-01DOI: 10.1109/ICIMW.2004.1422236
V. Kulish, A. Lysenko, I.G. Majornikov
A possibility to construct the powerful source of femto-second wave packages is analyzed. The method as well as a design variant of the system for forming such packages (the multi-harmonic two-stream superheterodyne free electron laser - MTSFEL) are proposed. A characteristic feature of the klystron model considered is the use of the method of synchronous electron beam compression within the interaction MTSFEL volume. It is shown that especially short wave packages (units-tens femto-second) can be obtained in such a way.
{"title":"A two-stream free electron laser for generation of the electromagnetic femto-second wave packages","authors":"V. Kulish, A. Lysenko, I.G. Majornikov","doi":"10.1109/ICIMW.2004.1422236","DOIUrl":"https://doi.org/10.1109/ICIMW.2004.1422236","url":null,"abstract":"A possibility to construct the powerful source of femto-second wave packages is analyzed. The method as well as a design variant of the system for forming such packages (the multi-harmonic two-stream superheterodyne free electron laser - MTSFEL) are proposed. A characteristic feature of the klystron model considered is the use of the method of synchronous electron beam compression within the interaction MTSFEL volume. It is shown that especially short wave packages (units-tens femto-second) can be obtained in such a way.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74294749","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}
Pub Date : 2004-01-01DOI: 10.1109/ICIMW.2004.1422281
A. Vertiy, S. Gavrilov, V. Stepanyuk, A. Salman
A new type of the mm-waves wire antennas (undulator antennas) is suggested and investigated in the frequency band 26-38.5 GHz. Calculations of the electric field radiation were conducted in the far zone at different frequencies for the undulator antennas with wires bent in shape of sinusoid. Experimental results showed that there are such working regimes of the undulator antennas excited by the traveling current wave, when the undulator antenna radiation is transversely-polarized broadside radiation, which sharply directed with insignificant level of the side lobes. Investigations of the undulator radiation characteristics showed its efficiency for employing as a basic element in different mm-wave devises, for example in aperture arrays.
{"title":"mm-wave radiation by the undulator type wire antennas","authors":"A. Vertiy, S. Gavrilov, V. Stepanyuk, A. Salman","doi":"10.1109/ICIMW.2004.1422281","DOIUrl":"https://doi.org/10.1109/ICIMW.2004.1422281","url":null,"abstract":"A new type of the mm-waves wire antennas (undulator antennas) is suggested and investigated in the frequency band 26-38.5 GHz. Calculations of the electric field radiation were conducted in the far zone at different frequencies for the undulator antennas with wires bent in shape of sinusoid. Experimental results showed that there are such working regimes of the undulator antennas excited by the traveling current wave, when the undulator antenna radiation is transversely-polarized broadside radiation, which sharply directed with insignificant level of the side lobes. Investigations of the undulator radiation characteristics showed its efficiency for employing as a basic element in different mm-wave devises, for example in aperture arrays.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75143239","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}
Pub Date : 2004-01-01DOI: 10.1109/ICIMW.2004.1422244
J. Sirigiri, M. Shapiro, R. Temkin
We present the design of a continuously tunable 330 GHz, 100 W CW gyrotron oscillator with a bandwidth of 2 GHz. The results have been obtained with MAGY, a nonlinear, nonstationary code. The physics of continuous tuning of a gyrotron by varying the operating magnetic field are discussed. The design is based on recent experimental observations of a wideband frequency tuning in a 250 GHz, 50 W CW gyrotron oscillator.
{"title":"Wideband continuous frequency tunable 330 GHz gyrotron oscillator","authors":"J. Sirigiri, M. Shapiro, R. Temkin","doi":"10.1109/ICIMW.2004.1422244","DOIUrl":"https://doi.org/10.1109/ICIMW.2004.1422244","url":null,"abstract":"We present the design of a continuously tunable 330 GHz, 100 W CW gyrotron oscillator with a bandwidth of 2 GHz. The results have been obtained with MAGY, a nonlinear, nonstationary code. The physics of continuous tuning of a gyrotron by varying the operating magnetic field are discussed. The design is based on recent experimental observations of a wideband frequency tuning in a 250 GHz, 50 W CW gyrotron oscillator.","PeriodicalId":13627,"journal":{"name":"Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75778501","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}
Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004.
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