16 January最新文献

{"title":"Influence of Surface Recombination on the Rate of Electron Leakage in Ridge-Waveguide Injection Lasers","authors":"H. Wünsche, H. Wenzel","doi":"10.1002/PSSA.2211110141","DOIUrl":"https://doi.org/10.1002/PSSA.2211110141","url":null,"abstract":"Simple formulae for the rate of electron leakage in injection lasers are derived, which take into account the surface recombination and an arbitrary number of heterojunctions. Applied to RW-lasers, where the surface beside the ridge is close to the active layer, a considerable enhancement of the leakage rate by the surface recombination is obtained. The influences of internal recombination, of drift fields, and of some device parameters on this effect are quantitatively investigated. \u0000 \u0000 \u0000 \u0000Es werden einfache Formeln fur die Elektronenleckrate in Injektionslasern hergeleitet, welche die Oberflachenrekombination und beliebig viele Hetero-Ubergange berucksichtigen. Angewendet auf RW-Laser, bei denen die Oberflache seitlich des Stegs nahe an der aktiven Schicht liegt, ergibt sich ein spurbares Anheben der Leckrate durch die Oberflachenrekombination. Der Einflus der inneren Rekombination, von Driftfeldern und einiger Bauelementeparameter auf diesen Effekt wird quantitativ untersucht.","PeriodicalId":240242,"journal":{"name":"16 January","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124136368","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 Distribution of Si-Related Defects and Carrier Density in GaAs Crystals","authors":"J. Pastrňák, J. Oswald, I. Gregora, V. Vorlíček, M. Babinský","doi":"10.1002/PSSA.2211110137","DOIUrl":"https://doi.org/10.1002/PSSA.2211110137","url":null,"abstract":"The spatial distribution of luminescence intensity for edge emission and extrinsic Si related bands is studied for Si-doped LEC grown GaAs crystals. Free carrier distribution is determined from the halfwidth and peak position of intrinsic luminescence and from the position of coupled LO-phonon–plasmon modes in Raman spectra. An increase of the luminescence intensity with carrier concentration is observed up to n ≈ 1018 cm−3, the sharp decrease for higher concentrations is ascribed to Auger recombination. The temperature dependence of three Si-related luminescence bands at 1.35 eV (A), 1.2 eV (B), and 1.0 eV (C) is measured. The similarity of the temperature behaviour of the A band with EL2 centres supports its assignment to (Si–AsGa) donors. \u0000 \u0000 \u0000 \u0000[Russian Text Ignored].","PeriodicalId":240242,"journal":{"name":"16 January","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115059876","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":"Polarization Reversal Current Behaviour for Parallel and Antiparallel Rubbed Surface Stabilized Ferroelectric Liquid Crystals","authors":"S. S. Bawa, K. Saxena, S. Chandra","doi":"10.1002/PSSA.2211110133","DOIUrl":"https://doi.org/10.1002/PSSA.2211110133","url":null,"abstract":"The polarization reversal current response for parallel and antiparallel rubbed samples of a 3 μm thick sample of DOBAMBC are studied by applying triangular pulses of varying voltage. The antiparallel rubbed sample shows two peaks and parallel rubbed sample shows three peaks of polarization reversal. The third peak appears before the peak of bulk switching and the zero field point of the applied pulse. It is shown that the selective pretilt angles with the surface results in tilted or bent smectic layer to give the multipeak response of the polarization reversal current. \u0000 \u0000 \u0000 \u0000Das Polarisationsumkehrstromverhalten fur parallel und antiparallel geschliffene Proben einer 3 μm dicken DOBAMBC-Probe werden mit dreieckformig anwachsenden Spannungsimpulsen untersucht. Die antiparallel geschliffene Probe zeigt zwei Maxima und die parallel geschliffene Probe zeigt drei Maxima von Polarisationsumkehr. Das dritte Maximum erscheint vor dem Maximum des Volumenverhaltens und dem Nullfeldpunkt des angelegten Impulses. Es wird gezeigt, das die ausgewahlten Vorneigungswinkel mit der Oberflache zu einer gekippten oder gebogenen smektischen Schicht fuhren, die den Mehrfachmaximumrespons des Polarisationsumkehrstroms liefert.","PeriodicalId":240242,"journal":{"name":"16 January","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128294797","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":"Method of Determining Supersmall Dilatations in a Crystal Lattice","authors":"V. S. Haroutyunyan, P. H. Bezirganyan","doi":"10.1002/PSSA.2211110103","DOIUrl":"https://doi.org/10.1002/PSSA.2211110103","url":null,"abstract":"A method to measure supersmall dilatation lattice distortions in the range Δd/d ≈ 10−10 to 10−8 by a bicrystal wedge-shaped gap X-ray interferometer is predicted. \u0000 \u0000 \u0000 \u0000[Russian Text Ignored].","PeriodicalId":240242,"journal":{"name":"16 January","volume":"37 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113993731","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":"Note on the Crystal Structure of FeCoGe and FeNiGe","authors":"T. Kanomata, T. Goto","doi":"10.1002/PSSA.2211110143","DOIUrl":"https://doi.org/10.1002/PSSA.2211110143","url":null,"abstract":"","PeriodicalId":240242,"journal":{"name":"16 January","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134467602","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":"Electrical Properties of Zn3P2 at Room Temperature","authors":"K. Sieraňski, J. Szatkowski","doi":"10.1002/PSSA.2211110154","DOIUrl":"https://doi.org/10.1002/PSSA.2211110154","url":null,"abstract":"","PeriodicalId":240242,"journal":{"name":"16 January","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124631042","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":"Etude de la résistivité de couches minces polycristallines de MoSe2","authors":"J. C. Bernègde, A. Mallouky, J. Pouzet","doi":"10.1002/PSSA.2211110119","DOIUrl":"https://doi.org/10.1002/PSSA.2211110119","url":null,"abstract":"Des couches minces de MoSe2 deposees par pulverisation diode continue sont traitees par recuits, en presence de vapeur de selenium puis sous vide, de facon a obtenir des couches polycristallines stoechiometriques. La composition et la purete des couches sont contrǒlees par spectroscopie d'electrons. Leur homogeneite est etudiee a la microsonde electronique. La conductivite est mesuree entre 80 et 700 K. Les resultats experimentaux montrent que les couches sont homogenes et que la quantite d'oxygene presente dans les couches est tres faible. Les resultats des mesures electriques mettent en evidence l'existence de deux domaines de temperatures. A haute temperature (T ≫ 250 K) la conductivite est limitee par les joints de grains. Aux basses temperatures la variation de la conductivite avec la temperature verifie une loi en T−¼ ce qui correspond a une conduction par sauts a distance variable entre etats localises. \u0000 \u0000 \u0000 \u0000MoSe2 thin films deposited by dc diode sputtering are annealed under selenium atmospheric pressure to obtain stoichiometric polycrystalline films. The composition, purity, and homogeneity of the films are checked by electron spectroscopy and electron microprobe analysis. The temperature dependence of the electrical conductivity is measured between 80 and 700 K. The experimental results show that the films are homogeneous and that the oxygen content in the layers is very low. The electrical data reveal the existence of two temperature regions. At high temperature (T > 250 K) the conductivity is limited by grain boundary scattering. At low temperatures the conductivity varies with temperature according to a T−¼ law corresponding to hopping conduction via localized states.","PeriodicalId":240242,"journal":{"name":"16 January","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126658283","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":"On the Nature of Afterglow of the X-Ray Induced Luminescence in Crystalline and Glassy SiO2","authors":"I. Godmanis, W. Hohenau","doi":"10.1002/PSSA.2211110136","DOIUrl":"https://doi.org/10.1002/PSSA.2211110136","url":null,"abstract":"The X-ray induced luminescence and its afterglow is investigated in natural and synthetic quartz crystals as well as in different types of glassy SiO2. In all types of SiO2 the luminescence intensity cannot be correlated directly with the impurity content of the investigated samples. A comparison of luminescence afterglow measurements of crystalline samples containing different impurities indicates that at low temperatures the luminescence is caused by forbidden intracenter transitions (constant afterglow below 150 K) of radiation induced defects (oxygen vacancy–peroxy linkage). Above 180 K the decrease of the afterglow decay time is explained by additional thermally activated ((370 ± 50) meV) radiationless (Frank-Codon) transitions, competing the luminous transitions. At high temperatures an impurity dependent luminescence occurs, detectable till 800 K, whose afterglow behavior is to be connected with the well known thermoluminescence. As in the case of silver or copper doped quartz, because of its afterglow behavior, the luminescence of quartz glasses is attributed to intracenter excitations at isolated not yet identified luminescence centers. \u0000 \u0000 \u0000 \u0000Sowohl in naturlichen und synthetischen Quarzkristallen als auch in verschiedenen Quarzglastypen wird die Rontgenlumineszenz beschrieben. Die Intensitat der registrierten Lumineszenz kann in allen untersuchten SiO2-Typen nicht direkt mit dem Fremstoffgehalt korreliert werden. Ein Vergleich von Lumineszenz-Nachleuchtuntersuchungen bei kristallinen Proben mit unterschiedlichem Verunreinigungsgrad zeigt, das bei tiefen Temperaturen die Lumineszenz durch an sich verbotene innere Ubergange (konstimtes Nachleuchten unterhalb 150 K) strahlungsinduzierter Defekte (Sauerstoffleerstelle-Peroxydbindung) verursacht wird. Die Abnahme der oberhalb 180 K registrierten Abklingzeit des Nachleuchtens wird durch thermisch aktivierte ((370 ± 50) meV) strahlungslose Ubergange (Frank-Condon) erklart, die in Konkurrenz zu den lumineszierenden Ubergangen stehen. Bei hohen Temperaturen wird eine verunreinigungsabhangige Lumineszenz bis etwa 800 K beobachtbar, deren Nachleuchtverhalten mit der bekannten Thermolumineszenz zusammenhangt. Ebenso wie im Falle silber- oder kupferdotierter Quarze wird die Lumineszenz von Quarzglasern aufgrund ihres Nachleuchtverhaltens inneren Ubergangen, ansonsten isolierter Lumineszenzzentren, zugeschrieben, welche allerdings bis jetzt unidentifiziert sind.","PeriodicalId":240242,"journal":{"name":"16 January","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126684897","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":"Fundamental Optical Absorption Edge in MnIn2Te4 Single Crystals","authors":"G. A. Medvedkin, Y. Rud', M. Tairov","doi":"10.1002/PSSA.2211110131","DOIUrl":"https://doi.org/10.1002/PSSA.2211110131","url":null,"abstract":"The optical properties are studied in the region of the fundamental absorption edge of MnIn2Te4 single crystals (142m, defect stannite) oriented along (100) and (001). The width of the energy gap is measured to be Eg = 1.55, 1.425, and 1.41 eV, for the temperatures 77, 300, and 370 K, respectively. The α(ℏω) spectra are established to follow Urbach's rule throughout the temperature range studied, the steepness of the absorption edge remaining constant. Crystal annealing followed by fast cooling shifts the absorption edge longward by 50 meV, the exponential character of α(ℏω) persisting within the whole range T = 77 to 370 K. An analysis shows the optical absorption in the region of the fundamental edge to be governed by the sum of the effects of the density-of-states tails associated with a high concentration of lattice vacancies and of the electron-phonon interaction. The optical linear dichroism of the absorption edge of MnIn2Te4 crystals with defect stannite structure is discovered and studied. It is found that the crystals belonging to the tetragonal syngony, such as MnIn2Te4 (142m) and CuInSe2, CuInTe2 (142d), and exhibiting a weak tetragonal lattice deformation τ ≈ 0, reveal, in contrast to most chalcopyrites with τ > 0, a positive linear dichroism of transmittance close to Eg. Minimal direct transitions in MnIn2Te4 are allowed in the E ⊥ c polarization, the crystal splitting of the valence band at the Γ point being positive. \u0000 \u0000 \u0000 \u0000[Russian Text Ignored].","PeriodicalId":240242,"journal":{"name":"16 January","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126884845","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":"Substance Classification","authors":"","doi":"10.1002/pssa.2210990103","DOIUrl":"https://doi.org/10.1002/pssa.2210990103","url":null,"abstract":"","PeriodicalId":240242,"journal":{"name":"16 January","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1987-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129536028","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}