Browsing NTNU Open by Author "Karhu, Eric Andrew"

Now showing items 1-8 of 8

    • Band-edge modification and mid-infrared absorption of co-deposited FexZn1-xS thin films 

      Molland, Nelly-Ann; Ghadyani, Zahra; Karhu, Eric Andrew; Poggio, Stefano; Nematollahi, Mohammadreza; Kildemo, Morten; Reenaas, Turid Worren; BelBruno, Joseph; Gibson, Ursula (Journal article; Peer reviewed, 2015)
      The bandgap of iron-doped ZnS has been reported by others to change significantly under the addition of a few atomic percent of iron, which would have significant implications for solar energy. Here, thin films of FexZn1-xS ...

    • Er,Yb:GdAl3(BO3)4 laser passively Q-switched by MBE-grown Cr:ZnS thin films 

      Gorbachenya, Konstantin N.; Kisel, Victor E.; Yasukevich, Anatoly S.; Tolstik, Nikolai; Karhu, Eric Andrew; Furtula, Vedran; Sorokin, Evgeni; Maltsev, VA; leonyuk, N.; Galinis, A.; Lipinskas, T.; Gibson, Ursula; Sorokina, Irina T; Kuleshov, Nikolai V. (Chapter; Peer reviewed, 2017)

    • MBE-grown Cr:ZnS Thin Film Laser Media 

      Tolstik, Nikolai; Sorokin, Evgeni; Karhu, Eric Andrew; Polyakov, Stanislav; Gibson, Ursula; Sorokina, Irina T (Chapter, 2016)
      We report results of spectroscopic analysis of the first first laser-quality MBE-grown Cr:ZnS films. Comparison of spectral-luminescent properties with bulk Cr:ZnS indicates their good laser properties, opening the way ...

    • Nonlinear optical response and structural properties of MBE-grown Fe:ZnS films 

      Polyakov, Stanislav; Karhu, Eric Andrew; Zamiri, Reza; Moisset, Charles; Iliopoulos, Konstantinos; Vullum, Per Erik; Österberg, Ulf; Gibson, Ursula (Journal article; Peer reviewed, 2018)
      Fe-doped ZnS films of high optical quality were fabricated using vacuum vapor deposition. Preferential crystalline orientation and phase purity of the host ZnS films were increased by the addition of small amounts of Fe, ...

    • Optical Coatings as Active Media for Mid-Infrared lasers 

      Karhu, Eric Andrew; Tolstik, Nikolai; Sorokin, Evgeni; Furtula, Vedran; Sorokina, Irina T.; Gibson, Ursula (Chapter, 2016)
      Thin films of Cr and Fe-doped ZnS with high infrared transparency have been deposited by molecular beam epitaxy and show optical properties suitable for use as active media in mid-infrared laser applications.

    • Spectral-luminescent properties of vapor deposited Cr:ZnS thin films and their application as saturable absorbers for 1.5-μm erbium lasers 

      Tolstik, Nikolai; Sorokin, Evgeni; Karhu, Eric Andrew; Gorbachenya, Konstantin N.; Polyakov, Stanislav; Kisel, Victor E.; Kuleshov, Nikolai V.; Furtula, Vedran; Gibson, Ursula; Sorokina, Irina T (Journal article; Peer reviewed, 2018)
      We report the results of the extensive spectral-luminescent characterization including concentration quenching analysis of the first laser-quality vapor-deposited Cr:ZnS films, and demonstrate their use as saturable ...

    • Towards Mid-IR Waveguide Lasers: Transition Metal Doped ZnS Thin Films 

      Karhu, Eric Andrew; Tolstik, Nikolai; Sorokin, Evgeni; Polyakov, Stanislav; Zamiri, Reza; Furtula, Vedran; Østerberg, Ulf Lennart; Sorokina, Irina T; Gibson, Ursula (Chapter; Peer reviewed, 2016)
      Thin films of Cr and Fe-doped ZnS suitable for waveguide mid-IR applications, with well-isolated TM2+ peaks, and Cr2+ absorption and fluorescence comparable to bulk crystals were investigated. Raman data indicate that the ...

    • Vapor deposited Cr-doped ZnS thin films: Towards optically pumped mid-infrared waveguide lasers 

      Karhu, Eric Andrew; Ildstad, Charles Rutherford; Poggio, Stefano; Furtula, Vedran; Tolstik, Nikolai; Sorokina, Irina T; BelBruno, Joseph; Gibson, Ursula (Journal article; Peer reviewed, 2016)
      Compact, affordable mid-IR lasers require the development of gain materials in waveguide form. We report on the high vacuum deposition of Cr:ZnS films with concentration ranging from 1018-1020 dopants/cm3 . At low ...