Pub Date : 1998-09-14DOI: 10.1109/CLEOE.1998.718869
F. Druon, G. Chériaux, A. Maksimchuk, G. Mourou
Chirped Pulse Amplification (CPA) allowed the development of ultrashort, high intensity lasers. For many applications, laser users are interested in reaching the highest intensity focused on target. Often neglected, the spatial quality of the beam is crucial in this regard(1). Wave-front distortions can significantly affect this spatial quality and thus severely reducing the attainable focused intensity. In fact, the wave-front of multi-Terawatt lasers, because of thermal effects and the size of optical elements, features sizeable distortions. The correction of the wave-front and a better confinement of the energy is thus a solution much less expensive than adding one more amplifier stage to the laser chain to actually obtain the same peak intensity. To quantify this decrease in the peak focused intensity, we use the normalized Strehl intensity which is the ratio of the peak intensity at focus of a beam with a distorted wave-front to that of the same beam without distortions. We present, in this paper, the wave-front correction of a femtosecond TeraWatt CPA lasers using an Achromatic Three-Wave Lateral Shearing Interferometer (ATWLSI)(2) and a deformable mirror.
{"title":"Wave-Front Correction of Femtosecond TeraWatt Laser Using a Deformable Mirrors","authors":"F. Druon, G. Chériaux, A. Maksimchuk, G. Mourou","doi":"10.1109/CLEOE.1998.718869","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.718869","url":null,"abstract":"Chirped Pulse Amplification (CPA) allowed the development of ultrashort, high intensity lasers. For many applications, laser users are interested in reaching the highest intensity focused on target. Often neglected, the spatial quality of the beam is crucial in this regard(1). Wave-front distortions can significantly affect this spatial quality and thus severely reducing the attainable focused intensity. In fact, the wave-front of multi-Terawatt lasers, because of thermal effects and the size of optical elements, features sizeable distortions. The correction of the wave-front and a better confinement of the energy is thus a solution much less expensive than adding one more amplifier stage to the laser chain to actually obtain the same peak intensity. To quantify this decrease in the peak focused intensity, we use the normalized Strehl intensity which is the ratio of the peak intensity at focus of a beam with a distorted wave-front to that of the same beam without distortions. We present, in this paper, the wave-front correction of a femtosecond TeraWatt CPA lasers using an Achromatic Three-Wave Lateral Shearing Interferometer (ATWLSI)(2) and a deformable mirror.","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124391400","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.719063
T. Winstone, C. Danson, R. Allott, G. Booth, J. Collier, A. Damerell, C. Edwards, A. Frackiewicz, P. Flintoff, S. Hancock, M. Harman, P. Hatton, S. Hawkes, M. Hutchinson, C. Hernandez-Gomez, J. Leach, W. Lester, D. Neely, M. Notley, D. Pepler, C. Reason, D. A. Rodkiss, I. Ross, J. Walczak, R. Wellstood, R. Wyatt, B. Wyborn
The VULCAN high power laser system is an eight beam Nd:glass (1.053 μm) system capable of delivering pulse lengths of 300 ps - 10 ns and energies of 250 J per beam (at 1 ns) on six 108 mm diameter beams and 500 J per beam (at 1 ns) on two 150 mm diameter backlighter beams. Furthermore VULCAN in high power mode is capable of single pulse powers in excess of 35 TW in pulses as short as 700 fs using the chirped pulse amplification (CPA)1 technique. CPA avoids the non-linear effects of propagating an ultrashort pulse through the amplifier glass by stretching the pulse prior to amplification.
{"title":"VULCAN: A Versatile Ultra High Power Nd: Glass Laser System","authors":"T. Winstone, C. Danson, R. Allott, G. Booth, J. Collier, A. Damerell, C. Edwards, A. Frackiewicz, P. Flintoff, S. Hancock, M. Harman, P. Hatton, S. Hawkes, M. Hutchinson, C. Hernandez-Gomez, J. Leach, W. Lester, D. Neely, M. Notley, D. Pepler, C. Reason, D. A. Rodkiss, I. Ross, J. Walczak, R. Wellstood, R. Wyatt, B. Wyborn","doi":"10.1109/CLEOE.1998.719063","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.719063","url":null,"abstract":"The VULCAN high power laser system is an eight beam Nd:glass (1.053 μm) system capable of delivering pulse lengths of 300 ps - 10 ns and energies of 250 J per beam (at 1 ns) on six 108 mm diameter beams and 500 J per beam (at 1 ns) on two 150 mm diameter backlighter beams. Furthermore VULCAN in high power mode is capable of single pulse powers in excess of 35 TW in pulses as short as 700 fs using the chirped pulse amplification (CPA)1 technique. CPA avoids the non-linear effects of propagating an ultrashort pulse through the amplifier glass by stretching the pulse prior to amplification.","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114480810","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.719321
Y. Hong, J.M. Tang, K. Shore
Optical phase conjugation through nearly degenerate four-wave mixing (NDFWM) in semiconductor lasers has attracted considerable attention in recent years since being first demonstrated by Nakajima and Frey[ 1 ]. Such interest arises due to the very high conjugate reflectivity of order 30-40dB which can be achieved owing to the amplifying effect of the semiconductor gain medium and cavity enhancement of mixing process. However, most previous experimental and theoretical work has placed emphasis on the weak signal case, where the injection signal acts only as a small perturbation of free-running laser diode. It is only very recently that a theoretical analysis of NDFWM in a semiconductor laser subject to strong probe injection power has been presented[2].
{"title":"Optical Phase Conjugation Using Four-Wave Mixing in Laser Diodes Subject to Strong Probe Injection Power","authors":"Y. Hong, J.M. Tang, K. Shore","doi":"10.1109/CLEOE.1998.719321","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.719321","url":null,"abstract":"Optical phase conjugation through nearly degenerate four-wave mixing (NDFWM) in semiconductor lasers has attracted considerable attention in recent years since being first demonstrated by Nakajima and Frey[ 1 ]. Such interest arises due to the very high conjugate reflectivity of order 30-40dB which can be achieved owing to the amplifying effect of the semiconductor gain medium and cavity enhancement of mixing process. However, most previous experimental and theoretical work has placed emphasis on the weak signal case, where the injection signal acts only as a small perturbation of free-running laser diode. It is only very recently that a theoretical analysis of NDFWM in a semiconductor laser subject to strong probe injection power has been presented[2].","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114375816","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.719507
A. Ionin, A. Kotkov, A. Kurnosov, A. Napartovich, L. Seleznev, N. Turkin
First overtone (FO, ΔV=2) CO laser characteristics are studied both experimentally and theoretically. Fundamental band (ΔV=1) lasing is totally suppressed by intracavity optical filter. First overtone (FO) lasing in the experiment takes place between high vibrational levels (up to 30) corresponding to the spectral range of 2.7-3.6 µm. The e-beam controlled discharge laser parameters are varied in the following ranges: gas temperature 100-300 K, gas density 0.05 - 0.5 Amagat; 0 - 80% of helium and 60 - 97% [Illegible] nitrogen fraction in mixture CO:N2:He; the specific input energy up to 1 00 J/1 Amagat; pumping pulse length 20 - 1000 µs.
{"title":"First Overtone CO Laser with Suppressed Fundamental Band Lasing","authors":"A. Ionin, A. Kotkov, A. Kurnosov, A. Napartovich, L. Seleznev, N. Turkin","doi":"10.1109/CLEOE.1998.719507","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.719507","url":null,"abstract":"First overtone (FO, ΔV=2) CO laser characteristics are studied both experimentally and theoretically. Fundamental band (ΔV=1) lasing is totally suppressed by intracavity optical filter. First overtone (FO) lasing in the experiment takes place between high vibrational levels (up to 30) corresponding to the spectral range of 2.7-3.6 µm. The e-beam controlled discharge laser parameters are varied in the following ranges: gas temperature 100-300 K, gas density 0.05 - 0.5 Amagat; 0 - 80% of helium and 60 - 97% [Illegible] nitrogen fraction in mixture CO:N2:He; the specific input energy up to 1 00 J/1 Amagat; pumping pulse length 20 - 1000 µs.","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114987952","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.719281
M. Schmid, R. Weber, H. Weber
Longitudinal diode laser pumping results in pronounced inhomogeneous heating of the laser material. This heat distribution affects the quality of a beam passing through the crystal due to thermal dispersion and thermal expansion.
{"title":"Modeling of Thermal Birefringence in Longitudinal Diode-Pumped Nd:YAG Laser Systems","authors":"M. Schmid, R. Weber, H. Weber","doi":"10.1109/CLEOE.1998.719281","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.719281","url":null,"abstract":"Longitudinal diode laser pumping results in pronounced inhomogeneous heating of the laser material. This heat distribution affects the quality of a beam passing through the crystal due to thermal dispersion and thermal expansion.","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"224 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117005849","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.718936
M. A. Noginov, G. Loutts, N. Noginova, M. Warren, C. Jackson, C. Bonner, R. Rakhimov, H. Ries
In work [1] we have studied photoinduced absorption, associated with it refraction index change, and holographic grating recording in Mn doped yttrium orthoaluminate (Mn:YAlO3). We have shown Mn:YAlO3 to be a promising material for optical storage and holography. In the present work, we spectroscopically investigate Mn ions in different valence states as well as transitions between different valence states responsible for photoinduced coloration of Mn:YAlO3.
{"title":"Spectroscopic Characterization of Mn:YAIO/sub 3/, Material for Holographic Recording and Optical Data Storage","authors":"M. A. Noginov, G. Loutts, N. Noginova, M. Warren, C. Jackson, C. Bonner, R. Rakhimov, H. Ries","doi":"10.1109/CLEOE.1998.718936","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.718936","url":null,"abstract":"In work [1] we have studied photoinduced absorption, associated with it refraction index change, and holographic grating recording in Mn doped yttrium orthoaluminate (Mn:YAlO3). We have shown Mn:YAlO3 to be a promising material for optical storage and holography. In the present work, we spectroscopically investigate Mn ions in different valence states as well as transitions between different valence states responsible for photoinduced coloration of Mn:YAlO3.","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117038879","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.719133
M. Greally, M. Adams
A theme of current VCSEL research is the quest for single-transverse mode operation, especially at high power levels. Monomode output is required for many VCSEL applications using both free-space propagation and the superior fibre-coupling properties of VCSELs. The oxide aperture approach has been remarkably successful in this respect, and a record single-mode power of 4.8 mW has been reported. Here we investigate the potential of a somewhat simpler approach - that of patterning the top reflector in a VCSEL in order to obtain sufficient waveguiding to confine a single transverse mode.
{"title":"New Approach to Transverse Mode Control in VCSELs","authors":"M. Greally, M. Adams","doi":"10.1109/CLEOE.1998.719133","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.719133","url":null,"abstract":"A theme of current VCSEL research is the quest for single-transverse mode operation, especially at high power levels. Monomode output is required for many VCSEL applications using both free-space propagation and the superior fibre-coupling properties of VCSELs. The oxide aperture approach has been remarkably successful in this respect, and a record single-mode power of 4.8 mW has been reported. Here we investigate the potential of a somewhat simpler approach - that of patterning the top reflector in a VCSEL in order to obtain sufficient waveguiding to confine a single transverse mode.","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122030188","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.719572
O. Hollricher, P. Spitzig, M. Fischer, O. Marti
{"title":"Polarisation Resolved Measurements of Mode Structures of Vertical Cavity Surface Emitting Laser Diodes Investigated with a SNOM","authors":"O. Hollricher, P. Spitzig, M. Fischer, O. Marti","doi":"10.1109/CLEOE.1998.719572","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.719572","url":null,"abstract":"","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"444 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125766216","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.719356
A. Cavalleri, K. Sokolowski-Tinten, J. Bialkowski, D. von der Linde
Time of flight (TOF) distributions of evaporated particles from the surface of GaAs have been measured in order to determine its maximum temperature during femtosecond irradiation (100 fs, 620 nm). A quadrupole mass spectrometer (QMS) provides the TOF distribution of a given particle mass after laser excitation.
{"title":"Time of Flight Measurement During Femtosecond Laser Ablation of Gallium Arsenide","authors":"A. Cavalleri, K. Sokolowski-Tinten, J. Bialkowski, D. von der Linde","doi":"10.1109/CLEOE.1998.719356","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.719356","url":null,"abstract":"Time of flight (TOF) distributions of evaporated particles from the surface of GaAs have been measured in order to determine its maximum temperature during femtosecond irradiation (100 fs, 620 nm). A quadrupole mass spectrometer (QMS) provides the TOF distribution of a given particle mass after laser excitation.","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125789874","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 : 1998-09-14DOI: 10.1109/CLEOE.1998.719522
W. Husinsky, P. Homolka, R. Biowski, C. Blaas, I. Baumgartner, G. Grabner
Corneal grafts are needed in ophthalmology for curative surgery on a regular basis. Thus transplants are often used in connatal abnormalities like a dermoid, to replace scarred tissue or in healing dystrophical defects like pemphigoid. There are several possibilities for their production, the most common being mechanical shaping and cutting of donor tissue.
{"title":"Excimer Laser Corneal Shaping System: Principles, Realization and Clinical Applications","authors":"W. Husinsky, P. Homolka, R. Biowski, C. Blaas, I. Baumgartner, G. Grabner","doi":"10.1109/CLEOE.1998.719522","DOIUrl":"https://doi.org/10.1109/CLEOE.1998.719522","url":null,"abstract":"Corneal grafts are needed in ophthalmology for curative surgery on a regular basis. Thus transplants are often used in connatal abnormalities like a dermoid, to replace scarred tissue or in healing dystrophical defects like pemphigoid. There are several possibilities for their production, the most common being mechanical shaping and cutting of donor tissue.","PeriodicalId":404067,"journal":{"name":"CLEO/Europe Conference on Lasers and Electro-Optics","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126154903","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}
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