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Volume 15, Issue 11
Displaying 1-26 of 26 articles from this issue
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Shigeo SHIONOYA1987 Volume 15 Issue 11 Pages 825
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSDownload PDF (102K) -
Tatsuo YAJIMA1987 Volume 15 Issue 11 Pages 826-831
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSA free-style essay is presented on such subjects as a historical view of ultrashort pulse generation, coherence of ultrashort light pulses, and studies of ultrafast phenomena not only by ultrashort light pulses.View full abstractDownload PDF (726K) -
FundamentalsTetsuro KOBAYASHI1987 Volume 15 Issue 11 Pages 832-841
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSTwo processes which are essential to generate ultrashort optical pulses are described. They are 1) producing/providing the broad-band optical spectra and 2) controlling the phase relation between the optical frequency components.
Additionally, typical methods of ultrashort optical pulse generation, i. e. modelocking, electrooptic gates, an optical pulse synthesizer, and…, are summarized.View full abstractDownload PDF (1024K) -
Kenjl TORIZUKA, Mikio YAMASHITA, Takuzo SATO1987 Volume 15 Issue 11 Pages 842-848
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSRecent investigations done in ETL on a femtosecond-pulse dye laser system are reviewed. Experimental techniques for generation and application of femtosecond pulses are described.View full abstractDownload PDF (628K) -
Hiromasa ITO1987 Volume 15 Issue 11 Pages 849-854
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSIt is quite important to generate optical pulses from semiconductor diode lasers with short pulsewidth and high peak power. Due to the compactness and capability of carrier injection of the diode laser, short optical pulses are well generated using a compact and simple system. These pulses are expected to be utilized not only in the optical communication, but also a wide variety of optoelectronic applications. This paper describes the generation of short optical pulses from semiconductor diode lasers, as well as the parameter dependence of the diode laser on the characteristics of short pulse generation.View full abstractDownload PDF (583K) -
Shuntaro WATANABE1987 Volume 15 Issue 11 Pages 855-862
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe present status of short pulse excimer lasers is described with an enphasis on XeCl, KrF and ArF. Main contents are (1) the gain spectra of excimer lasers, (2) short pulse generation and pulusewidth measurementat the excimer wavelengths, (3) scaling of peak power with regard to absorption, amplified spontaneous emission, and dispersion of optical elements. Typical short pulse excimer laser systems are summalized. Finally the prospect of applications such as multiphoton process are presented.View full abstractDownload PDF (692K) -
Akihiro MORIMOTO1987 Volume 15 Issue 11 Pages 863-868
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThis paper descrives the overview of recent developments on ultrashort pulse generation in solid state lasers.Traditional lasers such as Nd: glass lasers and Nd: YAG lasers generate more and more stable, higher power, and shorter optical pulses. “New lasers” such as Nd: YLF lasers, alexandrite lasers, and so on have become ultrashort pulse lasers. Pumping technique using laser diodes has been providing new horizen on ultrashort solid state lasers.View full abstractDownload PDF (607K) -
Masataka NAKAZAWA1987 Volume 15 Issue 11 Pages 869-886
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSRecent progress on optical pulse compression techniques, optical solitons, and soliton lasers has been discussed. It is shown that nonlinear pulse propagation in single-mode fibers, which includes self-phase modulation and group velocity dispersion, plays an important role in making linearly chirped rectangular pulses, resuiting in efficient compression with a grating pair. The self steepening effect, a third-order dispersion, and the stimulated Raman scattering, which would deteriorate the compression characteristics, have been discussed in dctail. For a negative GVD region, an optical soliton described with a nonlinear schrodinger equation can be creiatcd by balancing SPM with GVD. A soliton laser by means of a color center Iaser and a fiber Raman soliton laser are discussed in terms of a perturbation theory.View full abstractDownload PDF (1773K) -
Yuzo ISHIDA1987 Volume 15 Issue 11 Pages 887-895
Published: November 28, 1987
Released on J-STAGE: July 30, 2010
JOURNAL FREE ACCESSRecent progress of ultrashort pulse lasers and pulse compression techniques has allowed us to generate pulses with duration of the order of 10 fs or less.
The development of measurement techniques is also necessary for characterizing the ultrashort pulses. Linear direct measurement combined with photodetectors and oscilloscopes or ultrafast streak camera is no longer adequate to temporally resolve these pulses. Instead, various nonlinear correlation methods based on the nonlinear optical processes with time resolution of subpicosecond or femtosecond are proposed and demonstrated.
The basic concept, advantages and limitations of the methods including the recent development are discussed here.View full abstractDownload PDF (874K) -
Yutaka TSUCHIYA1987 Volume 15 Issue 11 Pages 896-904
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSRecent measuring technology for various types of ultrashort optical pulses using ultrafast streak cameras and optical oscilloscopes are reviewed. The optical oscilloscope is a conceptually new electron-optical instrument, in which two advanced technologies: streak camera and oscilloscope, are combined in one unit.View full abstractDownload PDF (1129K) -
Yoshio CHO1987 Volume 15 Issue 11 Pages 905-913
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSIn spite of recent advance in high-speed electronics reaching pico-second time regime, instrumentation means for their evaluations and testings are lacking. Pure electrical means is pointed out to have an inevitable limitation on its speed. Optical means can provide very short light pulses, which might be utilized to overcome the limitation in pure electrical means. Optical sampling technique is based upon recent availability of this very short optical pulse. Various optical sampling techniques are reveiewed on the general common concept of samplingtechnique and advantages of optical sampling are stressed.View full abstractDownload PDF (934K) -
Masahiro MATSUOKA, Hiroki NAKATSUKA1987 Volume 15 Issue 11 Pages 914-922
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSMeasurements of the relaxation times T1 and T2 of a two-level system by nonlinear transient spectroscopic methods are discussed, where delayed incident pulses are assumed to have correlation times much shorter than T1 or T2 but varied widths. In particular, a delayed degenerate four-wave mixing (photon echoe) and apump-and-probe type transmission measurement with incoherent long pulses are considered in detail, and a principle of their use for ultrafast spectroscopy is clarified. If the field is steady and T1>>T2, the time resolutionof T2measurement by the delayed four-wave mixlng is determined by the field correlation, therefore by the spectral width of the incident light irrespective of the pulse width. The time resoution of the T1 measurement by the pump-and-probe method is determined by the intensity correlation of the incident light, whereasthe one by the delayed four-wave mixing by a higher order correlation.View full abstractDownload PDF (892K) -
Toshiaki HATTORI, Takayoshi KOBAYASHI1987 Volume 15 Issue 11 Pages 923-929
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThree types of short-time measurements using temporally incoherent light instead of short pulses are described. Electronic dephasing in a polydiacetylene film, vibrational dephasing in dimethylsulfoxide liquid, and relaxation of optical Kerr effect in CS2 were observed with femtosecond time resolution. General applicability the ultrafast measument by various types of optical nonlinear processes using incoherent light was confirmed.View full abstractDownload PDF (740K) -
Masamitsu HIRAI1987 Volume 15 Issue 11 Pages 930-940
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSFormation mechanism of point defects in alkali halide crystals is introduced from a point of view on theultra fast relaxation process. Point defects (color centers) are produced in the crystals under irradiation ofionizing radiation or photons with photon energy larger than the band gap energy of the crystals. The first productis the positive hole which is localized in a period of several lattice viblations to form an X2- molecule (center) in a <110> direction in the crystal. Capture of a conduction electron by the X2- center creates the socalledself trapped exciton (STE), from which the intrinsic Luminescence and the point defect formation occur.The process starting by the ultra short pulse excitation and ending by the creation of the color centers is anultra fast phenomenum within a range between several picoseconds and several hundred picoseconds, andgives fundamental knowledge on the defect formation induced by the hole-or electron-lattice interaction.View full abstractDownload PDF (1143K) -
Yasuaki MASUMOTO1987 Volume 15 Issue 11 Pages 941-947
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSPopulation mixing and time-resolution techniques were applid to study the dynamical carrier processes inGaAs-AlGaAs superlattices under the perpendicular electric field.Competitive nature of ultrafast processes ofphoto-excited electron-hole pairs, exciton formation and pair ionization followed by tunneling through barriers, are clarified under the various electric field.View full abstractDownload PDF (744K) -
Yusaburo SEGAWA, Yoshinobu AOYAGI1987 Volume 15 Issue 11 Pages 948-951
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSTime resolved photoluminescence spectra of two-dimensional excitons in a GaAs supperlattice were observed by a picosecond dye laser. The relaxation times of the photo-excited excitons and carriers depend on the excitaion laser wavelength, and they are on the order of picosecond.View full abstractDownload PDF (362K) -
Relaxations of Excitonic Polaritons and Excitonic Magnetic PolaronsYasuo OKA, Ken-ichi NAKAMURA, Izuru SOUMA1987 Volume 15 Issue 11 Pages 952-958
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSStudy is reported on the picosecond spectroscopy of relaxation processes in exciton systems in semiconductors by using a single-photon-counting set up developed by the authors. Excitonic emissions in ZnTe is the first topic, which show the dynamical aspect of the polaritons near the bottleneck. Time evolution of the resonance Raman processes are observable in real time in the polariton emissions. The second topic is excitonic magnetic polarons in Cd1-xMnxTe, where the dynamics of the spin-correlated excitons with Mn ions is discussed.View full abstractDownload PDF (763K) -
Keitaro YOSHIHARA1987 Volume 15 Issue 11 Pages 959-965
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSStudies on intramolecular vibrational energy redistribution in the lowest excited electronic manifold are reviewed based on absorption, fluorescence, and ionization spectroscopy. A new method of “photochemical timing”is described for the vibrational mode dynamics of supersonically cooled trans-stilbene.View full abstractDownload PDF (676K) -
Noboru MATAGA1987 Volume 15 Issue 11 Pages 966-973
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSFundamental aspects of inter-and intramolecular photoinduced electron transfer (ET) and related phenomena studied by means of ultrafast laser spectroscopy as well as some related theoretical problems are discussed. Picosecond transient absorption spectral studies have demonstrated the existence of various ET states depending upon the solvents in the typical intramolecular exciplex systems and TICT compounds. Behaviors of geminate radical ion-pairs (RIP) formed in the course of photoinduced ET and electron photoejection have been studied in various systems. In the case of the geminate RIP of aromatic donor-acceptor systems in polar solvents, recombination rate has showed a bell-shaped energy gap dependence contrary to the fact that the bimolecular rate constant of fluorescence quenching due to ET is quite insensitive to the, relevant energy gap. These results have been interpreted by a new theory for the energy gap dependence of ET.View full abstractDownload PDF (965K) -
in Molecular OrganizatesIwao YAMAZAKI, Naoto TAMAI1987 Volume 15 Issue 11 Pages 974-982
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSExcitation energy transfer in restricted molecular geometries has been studied with vesicle surface, Langmuir-Blodgett monolayers and multilayers and a biological antenna pigment system. Picosecond time-resolved fluorescence spectra and decay curves revealed time behaviors of the excitation transfer characteristic of two-dimensional and stacking architectures. Distribution of guest molecules forms Fractal or Fractal-like structures in artificial molecular assemblies.View full abstractDownload PDF (905K) -
Yasushi KOYAMA1987 Volume 15 Issue 11 Pages 983-991
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSDeca-picosecond to nanosecond time-resolved, absorption spectroscopy applied to a set of cis-trans isomers of retinal, retinylideneacetaldehyde and β-carotene is summarized. No configurational changes have been detected in the singlet excited-state (S1) of either retinylideneacetaldehyde or β-carotene. Configurational changes (isomerization) have been detected in the triplet excited-state (T1) of retinal, retinylidene acetaldehyde and β-carotene. The rate of triplet isomerization was dependent on the starting ground-state configuration; it is the highest for the central-bent, unmethylated-cis configuration, and it is the lowest for the all-trans configuration.View full abstractDownload PDF (880K) -
Fumio TANAKA1987 Volume 15 Issue 11 Pages 992-1002
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSBiological functions of proteins can be understood in terms of protein dynamics. The results by theoretical considerations according to the method of molecular dynamics have predicted that protein structure is inherently dynamic in the time region of subpicosecond to picosecond. To observe such a fast dynamics of proteins a picosecond laser photolysis and a time-resolved fluorescence spectroscopy in the picosecond region are considered to be the most useful technique. In this review article, firstly the biological significance of protein dynamics and secondly, experimental evidences for picosecond dynamics of flavoproteins, and finally, the protein dynamics studied by the time-resolved fluorescence of tryptophanes are documented.View full abstractDownload PDF (1108K) -
Kiyoshi NAKAGAWA, Masatoshi SARUWATARI1987 Volume 15 Issue 11 Pages 1003-1010
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSOptical fiber communication systems are widely introduced into telecommunication networks since 1980's. The sub-nanosecond optical pulses are used in recent practical single-mode fiber transmission systems. This paper discusses the future possibility of ultra-short pulses application to communication systems. High-speed signal processing capability is discussed, and optical short-pulse generation, detection and multiplexing technology are described. It is expected that the future ultra-high speed communication systems will have the very large video communication service capability.View full abstractDownload PDF (706K) -
Yasuhiko ARAKAWA1987 Volume 15 Issue 11 Pages 1011-1015
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSIn this paper, high-speed optical devices having quantum well structures are discussed. These include quantum well lasers, quantum-confined Stark effect devices, and Optical-Stark effect devices.
It is expected that use of the quantum well structure leads to new types of ultrafast optical devices.View full abstractDownload PDF (462K) -
Seiji MUKAI, Masanobu WATANABE1987 Volume 15 Issue 11 Pages 1016-1019
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSVarious types of optically bistable semiconductor devices are reviewed. Characteristics of these devices desirous for their use in optical computers are discussed.View full abstractDownload PDF (470K) -
Takeshi KAMIYA1987 Volume 15 Issue 11 Pages 1020-1025
Published: November 28, 1987
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSMerits and existing problems of using pulsed semiconductor lasers as optical clock for optoelectronic integrate circuits (OEIC) are discussed. Examples are taken from the research efforts of the author's group on opto-electronic demultiplexing and multiplexing based either on fast photoconductive switch or on bistable semiconductor laser. Importance of developing optical circuit technology enabling multiple input/output optical connection is pointed out.View full abstractDownload PDF (607K)
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