Near field scanning optical microscopy for investigation of high power semiconductor lasers

В данной работе были исследованы карты распределения ближнего поля InGaAs/GaAs/AlGaAs полосковых инжекционных лазеров при различных токах накачки. Было показано, что в структурах, состоящих из двух резонансно связанных волноводов, наблюдается подавление мод высоких порядков.Near field intensity distributions of InGaAs/GaAs/AlGaAs lasers including broadened waveguides based on coupled large optical cavity (CLOC) structures were investigated. It was demonstrated that scanning near field optical microscopy gives direct proof of suppressing the transverse high-order mode lasing.Работа выполнена при поддержке РНФ (соглашение № 14-42-00006-П

InGaAlP/GaAs Injection Lasers of the Orange Optical Range (~600 nm)

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The role of the teacher of visualli impaired in the transition of a student with low vision from preschool to elementary school

V magistrski nalogi je obravnavan proces prehajanja otrok s slabovidnostjo iz predšolskega programa v prvi razred izobraževalnega programa s prilagojenim izvajanjem in dodatno strokovno pomočjo. Pri prehajanju v nov program lahko zaradi sprememb, ki sledijo, otroci doživljajo strahove in stres pred nečim neznanim. Prav tako se lahko podobna občutja pojavijo tudi pri starših in bodočih strokovnih delavcih, ki bodo otroka obravnavali. Vloga tiflopedagoga je optimizacija procesa prehajanja pri vseh vključenih – nudenje podpore otroku in njegovi družini kot tudi šoli, vsem zaposlenim ter vrstnikom. V magistrski nalogi se je s kvalitativnim raziskovalnim pristopom obravnavala študija primera prehoda petletnega fantka s prirojeno katarakto iz vrtca v osnovno šolo. Glavni cilj naloge je prikazati, kako s sodelovanjem pri načrtovanju in izvedbi tranzicije otroku s slabovidnostjo, staršem ter strokovnim delavcem na šoli omogočiti optimalen prehod in sprejem otroka v novo okolje ter opisati splošne smernice pri tiflopedagoškem načrtovanju obravnavanega prehoda. V raziskavo so bili poleg otroka vključeni še starši in strokovnjaki, ki so z učencem na vsakodnevni interakciji ter vrstniki. Tehnike zbiranja podatkov so potekale v različnih časovnih obdobjih, vse od otrokove vključenosti v vrtec do zaključka prvega polletja v prvem razredu. Rezultat začetnega zbiranja podatkov o otroku je celostna ocena otrokovega funkcioniranja pred vključitvijo v osnovno šolo. Nadaljnji rezultat zbiranja podatkov o bodočem učnem okolju ter upoštevanja celostne ocene otroka sta načrt o prilagoditvi notranjih in zunanjih prostorov osnovne šole ter evalvacija izvedenih prilagoditev. Rezultat analize celostne ocene otrok je predstavitev otroka, prilagoditev in metod dela učiteljskemu aktivu za prvi razred ter evalvacija učenčevega celostnega napredka ob koncu prvega polletja. Rezultat priprave delavnice je ozaveščanje vrstnikov o slepoti in slabovidnosti ter evalvacija uspešnosti le-te. Rezultat evalvacije učenčevega funkcioniranja v šoli ob koncu prvega polletja so tiflopedagoška priporočila za nadaljnje delo z učencem. Na podlagi pregledanih teoretičnih izhodišč in praktičnega udejstvovanja v procesu tranzicije so zbrane izluščene smernice za uspešno izvedbo procesa. Priložena je priprava na sestanek z učiteljskim aktivom, tabeli za ocenjevanje šolskega okolja ter podajanje priporočil glede prilagoditev šolskega okolja. Dodan je tudi formular, ki je lahko tiflopedagogu v pomoč pri organizaciji in pridobivanju podatkov o učbenikih za prihodnje šolsko leto. Na podlagi analize vseh pridobljenih podatkov je bilo ugotovljeno, da je prehod učenca potekal optimalno.This paper discusses the period of transition for children with low vision as they finish preschool education and progress to the first grade of an inclusive education programme with additional professional assistance. The transition into a new programme can be a very frightening and stressful experience for a child due to the so called unknown factor. Similar feelings can arise with parents and future professional workers, which will play their part in the upbringing of a said child. The role of the teacher of visually impaired is to optimize the transition process for all parties involved – to lend support to the child and its family, to help the school, its employees and the child\u27s peers. This paper studies an example of a transition of a five-year-old boy with a congenital cataract from kindergarten to elementary school with help of qualitative research method. Primary goal of this paper is to help coordinate and execute a successful plan with the child, its parents and professional workers at school, thereby enabling optimal transition and reception of a child in the new environment and describe the general guidelines of planning this transition. Along with the boy, its parents, peers and professional workers who interact with the boy on a daily basis were also included in research. Data gathering took place in different time intervals from the child\u27s integration in kindergarten to the conclusion of first semester in the first grade. The result of initial data gathering about the child is a comprehensive assessment of his functioning prior to his inclusion in elementary school. The subsequent result of data gathering focused on future educational environment and consideration of the comprehensive assessment of the child is the adaptation plan for external and internal elementary school facilities and an evaluation of these adjustments. The result of comprehensive child assessment analysis is an introduction of the child, adjustments and work methods to his teachers in the first grade and an evaluation of the student\u27s progress by the end of first semester. The result of setting up a workshop was to make the student\u27s peers aware of blindness and vision impairment and to evaluate the level of awareness they have. The result of child\u27s performance in school evaluation at the end of the first semester are professional recommendations by the teacher of visually impaired on how to work with the impaired student in the future. On the basis of examined theoretical standpoints and practical application in the process of transition extracted guidelines for an effective execution of the process have been determined. A preparation for a meeting with the teacher\u27s group is included as well as tables for school environment assessment and recommendations on school environment adjustments. A form is included as well, which a teacher of visually impaired might find helpful when organizing and gathering information on school books for the upcoming school year. An analysis of all acquired data has shown that the transition of a student was optimal

Room-temperature yellow-orange (In,Ga,Al)P–GaP laser diodes grown on (n11) GaAs substrates

We report room temperature injection lasing in the yellow–orange spectral range (599–605 nm) in (AlxGa1–x)0.5In0.5P–GaAs diodes with 4 layers of tensile-strained InyGa1–yP quantum dot-like insertions. The wafers were grown by metal–organic vapor phase epitaxy side-by-side on (811), (211) and (322) GaAs substrates tilted towards the direction with respect to the (100) surface. Four sheets of GaP-rich quantum barrier insertions were applied to suppress leakage of non-equilibrium electrons from the gain medium. Laser diodes having a threshold current densities of ~7–10 kA/cm2 at room temperature were realized for both (211) and (322) surface orientations at cavity lengths of ~1mm. Emission wavelength at room temperature ~600 nm is shorter by ~8 nm than previously reported. As an opposite example, the devices grown on (811) GaAs substrates did not show lasing at room temperature

Room-temperature yellow-orange (In,Ga,Al)P–GaP laser diodes grown on (n11) GaAs substrates

International audienceWe report room temperature injection lasing in the yellow–orange spectral range (599–605 nm) in (Al x Ga 1–x) 0.5 In 0.5 P–GaAs diodes with 4 layers of tensile-strained In y Ga 1–y P quantum dot-like insertions. The wafers were grown by metal–organic vapor phase epitaxy side-by-side on (811), (211) and (322) GaAs substrates tilted towards the direction with respect to the (100) surface. Four sheets of GaP-rich quantum barrier insertions were applied to suppress leakage of non-equilibrium electrons from the gain medium. Laser diodes having a threshold current densities of ~7–10 kA/cm 2 at room temperature were realized for both (211) and (322) surface orientations at cavity lengths of ~1mm. Emission wavelength at room temperature ~600 nm is shorter by ~8 nm than previously reported. As an opposite example, the devices grown on (811) GaAs substrates did not show lasing at room temperature