Yazar "Özgür, Ümit" için listeleme
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Active region dimensionality and quantum efficiencies of ingan leds from temperature dependent photoluminescence transients
Can, Nuri; Okur, Serdal; Monavarian, Morteza; Zhang, Fan; Avrutin, Vitaliy; Morkoç, Hadis; Teke, Ali; Özgür, Ümit (Spie-Int Soc Optical Engineering, 2015)Temperature dependent recombination dynamics in c-plane InGaN light emitting diodes (LEDs) with different well thicknesses, 1.5, 2, and 3 nm, were investigated to determine the active region dimensionality and its effect ... -
A comprehensive review of ZnO materials and devices
Özgür, Ümit; Alivov, YI.; Teke, Ali; Reshchikov, MA; Doğan, Seydi; Avrutin, V; Cho, SJ.; Morkoc, H. (Amer Inst Physics, 2005)The semiconductor ZnO has gained substantial interest in the research community in part because of its large exciton binding energy (60 meV) which could lead to lasing action based on exciton recombination even above room ... -
Excitonic fine structure and recombination dynamics in single-crystalline ZnO
Teke, Ali; Özgür, Ümit; Doğan, Seydi; Gu, Xing; Morkoç, Hadis; Nemeth, Bill; Nause, J.; Everitt, Henry O. (Amer Chemical Soc, 2004)The optical properties of a high quality bulk ZnO, thermally post treated in a forming gas environment are investigated by temperature dependent continuous wave and time-resolved photoluminescence (PL) measurements. Several ... -
Improvement of carrier injection symmetry and quantum efficiency in ıngan light-emitting diodes with mg delta-doped barriers
Zhang, F.; Can, Nuri; Hafiz, S.; Monavarian, M.; Das, S.; Avrutin, V.; Özgür, Ümit; Morkoç, Hadis (Amer Inst Physics, 2015)The effect of delta-doping of In0.06Ga0.94N barriers with Mg on the quantum efficiency of blue light-emitting-diodes (LEDs) with active regions composed of 6 (hex) 3-nm In0.15Ga0.85N is investigated. Compared to the reference ... -
Improvement of optical quality of semipolar (11(2)over-bar2) GaN on m-plane sapphire by in-situ epitaxial lateral overgrowth
Monavarian, Morteza; Izyumskaya, Natalia; Mueller, Marcus; Metzner, Sebastian; Veit, Peter; Can, Nuri; Das, Saikat; Özgür, Ümit (Amer Inst Physics, 2016)Among the major obstacles for development of non-polar and semipolar GaN structures on foreign substrates are stacking faults which deteriorate the structural and optical quality of the material. In this work, an in-situ ... -
Stimulated emission and time-resolved photoluminescence in rf-sputtered ZnO thin films
Özgür, Ümit; Teke, Ali; Liu, Chunli; Cho, S.J.; Morkoç, Hadis; Everitt, Henry O. (Amer Inst Physics, 2004)Stimulated emission (SE) was measured from ZnO thin films grown on c-plane sapphire by rf sputtering. Free exciton transitions were clearly observed at 10 K in the photoluminescence (PL), transmission, and reflection spectra ...
