• Broadband infrared and THz transmitting silicon core optical fiber 

      Sørgård, Trygve; Song, Seunghan; Vullum, Per Erik; Kores, Cristine; Mølster, Kjell Martin; Laurell, Fredrik; Hawkins, Thomas A.; Ballato, John; Österberg, Ulf Lennart; Gibson, Ursula (Peer reviewed; Journal article, 2020)
      Silicon waveguide structures are a viable alternative for the transmission of signals over a wide range of frequencies, and new fabrication methods are key to increased applications. In this work, THz transparency of ...
    • CO2 laser annealed SiGe core optical fibers with radial Ge concentration gradients 

      Wu, Wei; Balci, Mustafa H.; Song, Seunghan; liu, chunxin; Fokine, Michael; Laurell, Fredrik; Hawkins, Thomas A.; Ballato, John; Gibson, Ursula (Peer reviewed; Journal article, 2020)
      CO2 laser annealing of SiGe core, glass-clad optical fibers is a powerful technique for the production of single-crystal cores with spatially varying Ge concentrations. Laser power, laser scan speed and cooling air flow ...
    • Crystalline GaSb-core optical fibers with room-temperature photoluminescence 

      Song, Seunghan; Healy, Noel; Svendsen, Silje; Österberg, Ulf; Cuervo Covian, Alejandra; Liu, Jifeng; Peacock, Anna; Ballato, John; Laurell, Fredrik; Fokine, Michael; Gibson, Ursula (Journal article; Peer reviewed, 2018)
      Glass-clad, GaSb-core fibers were drawn and subsequently laser annealed. The asdrawn fibers were found to be polycrystalline, possess Sb inclusions, and have oxide contamination concentrations of less than 3 at%. Melting ...
    • Laser restructuring and photoluminescence of glass-clad GaSb/Si-core optical fibres 

      Song, Seunghan; Lønsethagen, Kristin; Laurell, Fredrik; Hawkins, Thomas A.; Ballato, John; Fokine, Michael; Gibson, Ursula (Journal article; Peer reviewed, 2019)
      Semiconductor-core optical fibres have potential applications in photonics and optoelectronics due to large nonlinear optical coefficients and an extended transparency window. Laser processing can impose large temperature ...
    • Laser structuring, stress modification and Bragg grating inscription in silicon-core glass fibers 

      Fokine, Michael; Theodosiou, Antreas; Song, Seunghan; Hawkins, Thomas A.; Ballato, John; Kalli, Kyriacos; Gibson, Ursula (Journal article; Peer reviewed, 2017)
      Semiconductor core fibers have numerous potential applications in optoelectronics and photonics, and the key to realizing these opportunities is controlled processing of the material. We present results on laser treatments ...
    • Si/GaSb Micro Core Glass fiber 

      Song, Seunghan (Master thesis, 2017)
      Semiconductor core glass fibers are a promising platform for optoelectronic and optical applications with an enormous potential. Glass fibers with homogeneous semiconductor cores have mainly studied so far, but recent ...
    • Single crystal semiconductor-core optical fiber* 

      Wu, Wei; Song, Seunghan; Balci, Mustafa H.; Laurell, Fredrik; Cantwell, Patrick; Ballato, John; Gibson, Ursula (Journal article; Peer reviewed, 2019)
      Semiconductor-core fibers are improved by removal of grain boundaries. We use a CO2 laser to process silicon-based cores; an alloying element reduces both the temperature and speed required for formation of a single crystal.