Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics最新文献

{"title":"Growth And Optical Properties Of Nonlinear Crystal Sr/sub 2/Be/sub 2/b/sub 2/O/sub 7/","authors":"Chuangtian Chen, Bai-chang Wu, Wen-xian Zeng, Xiquan Wu, N. Ye, Yu-Dong Zhang, Linhua Yu","doi":"10.1109/CLEOPR.1997.610758","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.610758","url":null,"abstract":"coefficient' is fairly constant in this temperature region. The fitted isentropic bandgaps are similar at all temperatures. The experimental points and the fitting curves are shown by the lower and upper curves at -40 and 60T, respectively, in Fig. 1 [(a) for BK7 and (b) for SF6]. Thermo-optic coefficients of SF6 and BK7 glasses are 7.86, 6.66, and 6.46; 2.54, 2.35 and 2.32 ppm/\"C at 0.85, 1.33, and 1.55 IJ-m, respectively. These optical constants are used to characterize many temperature-dependent optical parameters, namely, Abbe number, chromatic dispersions at the three optical windows and femtosecond laser pulses; and zero-dispersion wavlength. *Electrotechnical Laboratory, 1 -14 Umewno, l3ukuba 305, JAPAN","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124975273","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}

{"title":"New Classification Of Clinical Iaser Practical Application","authors":"T. Ohshiro, K. University","doi":"10.1109/CLEOPR.1997.611024","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.611024","url":null,"abstract":"the sinus node function is an alternative method of nonpharmacological treatments, although the skillful and troublesome technique is required. We developed a new simplified method without electrophysiological technique for laser sinus node modification, and investigated the efficacy and safety of this method. In six mongrel dogs, the lasertissue interactions by epicardial Nd:YAG laser irradiation were investigated by measuring the diameter and the depth of the irradiated lesions. Laser irradiations were performed from the head to the tail on the sinus node areas directed only by terminal groove for the visual landmark without electrophysiological technique until a 25% decrease in heart rate occurred in other six open-chest dogs. Mean heart rate and maximal heart rate could be significantly decreased from 128 2 4.7 to 101 t 4.4 bpm and from 187 t 1.8 to 144 t 9.3 bpm, respectively Sinus node recovery time (613 2 47 versus 861 t20 msec), corrected sinus node recovery time (185 t20 versus 236 & 33 msec), P wave duration and voltage (101 2 3 versus 105 2 3 msec and 1.4 t0.2 versus 1.3 i0.2 mV) and PQ interval (101 t3 versus 105 It 3 msec) were not affected. In all dogs, sinus rhythm was maintained without occurrence of any arrhythmias. This simplified method might be accepted as an alternative nonpharmacological treatment for inappropriate sinus tachycardia in patients with cardiac dysfunction.","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126129905","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}

{"title":"Lntegrated Semiconductor Optical Amplifier Waveguide Structures And Components","authors":"H. Melchior","doi":"10.1109/CLEOPR.1997.610625","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.610625","url":null,"abstract":"the 2D-RS signal intensities. The 2D-RS signal intensities at the central part of the particle distribution are plotted in Fig 3 as a function of the time after ablation for two different ambient pressures. It is found that the particles grow up more rapidly as an ambient pressure increased. The pafticle growth almost finished at about 10 ms after ablation at a He pressure of 10 Torr In summary, the whole process, where the Si atoms generated by laser ablation are converted into nano-particles by the condensation in the ambient gas, is visualized by the imaging laser spectroscopy.","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126934356","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}

{"title":"All Optical Switching In Rare-earth Doped Fibers","authors":"J. Arkwright, G. Atkins, Z. Brodzeli, J. Canning, M. Janos, P. Elango, M. Sceats, T. Whitbread","doi":"10.1109/CLEOPR.1997.610950","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.610950","url":null,"abstract":"The nonlinear response seen in rare-earth doped fibers is due to the change in absorption induced by optical pumping of the resonant transitions of the rare-earth ions. Since many rare-earth ions exhibit long-lived metastable states, these changes in absorption, and hence, the associated changes in refractive index, can be large for relatively modest absorbed pump powers. For example, typical values for the induced index change are of the order 1 part in lo6 for absorbed pump powers of a few milliwatts, and all-optical switching has been observed for pump powers as low as 1 mW. Since these rare-earths can also be used to form efficient fiber lasers it has been possible to use the lasing dynamics of the fibers to: 1) demonstrate a digital nonlinear behavior, by utilizing the clamping of the population inversion at threshold,’ and 2) improve the response times by using Q-switching induced stimulated depopulation of the excited state? A further advantage of this type of nonlinearity is that in-fiber Bragg reflection gratings can be readily incorporated into the nonlinear medium and can be used to give highly wavelength selective modulation of the transmitted signal. This has been demonstrated in two ways using the pump induced index change. Firstly by side pumping of a doped fiber grating in order to introduce a phase shift part of the way along the grating, which creates a transmission notch in the reflection band of the grating;3 and secondly by axial pumping of the doped fiber grating causing a shift in its reflection band such that a propagating signal positioned near the band-edge of the grating experiences a greater or lesser transmi~sivity.~ It is commonly assumed that to make use of these resonant nonlinearities, it is necessary to operate within, or close to, the rare-earth absorptions, which tends to introduce high losses at the signal wavelength. However, it has recently been demonstrated that the induced index change seen in rare-earth doped fibers is due not only to the localized changes in absorption of the optically pumped transitions themselves, but also to changes in absorption of all transitions that involve FRIDAY MORNING 1 CLEO/PACIFIC RIM / 265","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115221816","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}

{"title":"Thz Electro-optic Field Sensors","authors":"X. Zhang, Q. Wu, M. Litz","doi":"10.1109/CLEOPR.1997.610509","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.610509","url":null,"abstract":"","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122534837","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}

{"title":"Newly Designed Beam Shaper To Improve The M/sup 2/ Of The Diode-bar Beam To Pump An Intracavity-doubled Nd:YVO/sub 4/ Laser","authors":"T. Izawa, R. Uchimura, S. Matsui, T. Arichi, T. Yakuoh","doi":"10.1109/CLEOPR.1997.610322","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.610322","url":null,"abstract":"quality, although it falls to the flattering side in that it gives the non-ideal beam an ideal mark. This is due to the fact that in the IS0 definition this method does not take into account intensity ripples which are below 13.5% of the peak intensity value. One of the interpretations of the M' value is that it is the ratio of the actual focused beam waist, to that of a gaussian beam waist, given the same incident beam diameter and angle. In real life the high quality beam used here should have a focused beam size very close to an ideal gaussian. The results of 1.6 and 1.2 are both unrealistic represenlalions of the beam quality. All three methods yield the same result for a gaussian beam, while they are based on different characteristics of the gaussian distribution. Second moment method relies on the fact that gaussian distribution converges exponentially, therefore suppressing the quadratic radius factor at large radii. Knife edge method is a definition of enclosed energy at 68% of the total. Moving slit method, on the other hand, takes into account only the distance between the peak intensity point and 1 / e 2 point. When a reallife laser beam with a spherical phase front deviates significantly in intensity from any of these features of the gaussian distribution, one or more methods described here will fail to give a meaningful description of mode quality of the laser beam. We propose a method in which an aberration-free lens and a pin-hole is used in conjunction with the above mentioned M Z methods. Power throughput from the pin-hole and M 2 value of the beam after the pin-hole are both considered in describing the quality of a laser beam. 1. International Organization for Standardization, ISO/TC 172/SC 9/WG 1, Draft International Standard KO/ DIS 11 146.","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122758551","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}

{"title":"Lateral Light-coupling For Evanescent-field Guiding Of Cold Atoms","authors":"K. Sakaki, H. Ito, M. Ohtsu","doi":"10.1109/CLEOPR.1997.610363","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.610363","url":null,"abstract":"of excited states. In this study, first measurements of time and spatially varying fluorescence lifetimes of BaO observed in laser-ablation plumes of BaTiO, processes are reported. BaO molecules have been generated by laser-ablation of a BaTiO, target in ambient oxygen gas. The BaO A'Z+ (v = 4) band edge has been excited' [OPO, X = 535 nm, Ah = 10 pm (FWHM), At = 10 ns (FWHM)] and the resonant fluorescence signal within a point like observation volume 15 mm above the target has been analyzed. Figure 1 represents the measured fluorescence lifetime as a function of the delay time between the ablation laser (KrF) and the LIF probe laser (OPO) pulse. A higher collisional quenching rate is clearly visible for higher ambient oxygen gas pressures. The observed decrease in the lifetime at shorter delay times is related to a smaller plume volume and, hence, to a higher collision frequency. Fluorescence signal intensities were too weak, however, to be detected at delay times smaller than 20 ps. In a second experiment, 2D-LIF imaging measurements have been performed for different integration times of the IICCD. From these data, fluorescence lifetimes have been numerically determined within the observation plane. The result is represented in Fig. 2 for a delay time of 200 ps and for an ambient 0, pressure of 500 mTorr. The lifetime distribution looks rather homogeneous, which can be expected for the given delay time. The lifetime frequency diagram is shown in Fig. 3. The lifetime with the highest frequency corresponds well with the result of the single point measurement. The width of the distribution is mainly affected by shot to shot ablation plume fluctuations and by the signal-to-","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"234 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122528889","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}

{"title":"Monolithic Integration Of Cd/sub 1-x/Mn/sub x/Te Magnetoopfical Waveguide On GaAs Substrate","authors":"W. Zaets, K. Watanabe, K. Ando","doi":"10.1109/CLEOPR.1997.610926","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.610926","url":null,"abstract":"","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122966894","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}

{"title":"Photocurrent In Semiconductors Induced With Phase-sensitive Femtosecond Optical Pulses","authors":"Wei-liang Li, Jian-ying Zhou, Q. Luo","doi":"10.1109/CLEOPR.1997.610602","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.610602","url":null,"abstract":"was measured as 1 X cm-3, which is one order of magnitude higher than reported for InP. The net-carrier concentration increased after annealing the InAsP samples at 470°C for 3 min a N, atmosphere. The morphological damage after the diffusion was not found by interference contrast (Nomarsky) optical microscopy and secondary electron microscopy. Figure 2 shows the plot of diffusion depth versus diffusion time for the InP and InAsP samples after the annealing for 3 min at 470°C in an N, atmosphere. The straight lines fitted by the least squares to the data, indicates that the diffusion depth is linearly dependent on the square root of the diffusion time even in the submicrometer range. These results show that MOVPD allows to accurately control the diffusion of Zn acceptors in the submicrometer range for InAsP. The maximum hole concentration up to about 1 X 1019 cm13 is achieved. Such a highlydoped layer is also suitable for a new type of Ohmic contact layers. Finally, we have successfully demonstrated InAsP/InGaAs photodiodes with a 100 nm thick InAsP cap layer fabricated by diffusion using MOVPD. The very wide spectral response of 0.6-2.5 pm is obtained for these photodiodes. 1. H. Q. Hou, A. N. Cheng, H. H. Wieder, W. S. C. Chang, C. W. Tu, Appl. Phys. Lett. 63, 1833 (1993). Morio Wada, Mashahito Seko, Katsutoshi Sakakibara, Yoichi Kekiguchi, Jpn. J. Appl. Phys. 28, L1700 (1989). Zothn F. Paska, Dan Haga, Bo Will h , Appl. Phys. Lett. 60, 1594 (1 992). J. Wisser, M. Glade, H. J. Schmidt, K. Heime, J. Appl. Phys. 71, 3234 (1992). 5. Morio Wada, Haruo Hosomatsu, Appl. Phys. Lett. 64, 1265 (1994). 2.","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117035557","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}

{"title":"Analysis Of Five-step Asymmetric Coupled Quantum Wells For Large Field-induced Refractive Index Change","authors":"H. Feng, M. Sugiyama, J. Pang, K. Tada, Y. Nakano","doi":"10.1109/CLEOPR.1997.614116","DOIUrl":"https://doi.org/10.1109/CLEOPR.1997.614116","url":null,"abstract":"We report tunneling processes of carriers in asymmetric double quantum wells (ADQWs) of the Zn,-,Cd,Se/ZnSe system studied by the pump-probe absorption spectroscopy (PPAS) and the timeresolved photoluminescence (TRPL). The tunneling time of carriers as a function of the barrier thickness has been determined from the transient absorption and luminescence characteristics of the ADQW exciton states by comparing with calculation of the population rates of carriers and excitons in the ADQW sub-levels. Stimulated emission processes of the highly excited excitons in the ADQWs has also been studied, where the stimulation process is induced by the tunneling process. Zn,-,Cd,Se/ZnSe ADQW samples, prepared by the MBE and hot-wall epitaxy methods, consist of the narrow well (NW) of 15-30 A and the wide well (WW) of 70-80 A, which are separated by the ZnSe barrier of 34-270 A. The photoluminescence (PL) and PL excitation spectra show the evidence of the tunneling of carriers from NW to WW for thinner barrier samples. PPAS and TRPL have been made to deduce the tunneling times by using a femtosecond mode-locked Ti:sapphire laser system. Figure 1 shows the variation of differential transmission spectra for various delay times in the sample with the widths of NW apd WW and the barrier of 30,70 and 40 A, respectively. The spectra shown on the top of Fig. 1 are the PL and absorption spectra. The pump light of 10 nJ/pulse induces the absorption saturation of the NW exciton, which reaches the maximum at 11.3 ps. The recovery of the absorption saturation of NW exciton takes place within 40 ps after the pump excitation. In the 100 A-barrier sample, the recovery time of the NW exciton absorption saturation is much longer than that of the 40 A-barrier sample. The observed fast recovery of the NW absorption saturation is related to the tunneling process of carriers. Spectrallyintegrated differential absorption change of the 40 A-barrier sample is shown in Fig. 2 as a function of the delay time. The electron-and hole tunneling time through the 40 A barrier is determined to be 10 and 16 ps, respectively where a model of independent tunneling for electron and hole is used. The similar tunneling times of the electron and the hole indicates that the exciton tunneling process exists in the thin-barrier ADQWS.',~ In the case of 100 A-barrier sample, the electron and hole tunneling times are 6 and 160 ps respectively. The tunneling time of the camers measured by the TRPL is 1.3 ps-100 ps as the barrier widths vary from 34 to 270 A. It is concluded that the tunneling of the exciton becomes dominant with decreasing the barrier thickness. Stimulated emission effects have been investigated in the ADQW system. Figure 3 shows the stimulated emission spectra and the differential transmission spectra under high optical excitation of","PeriodicalId":260495,"journal":{"name":"Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128644179","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}