Characterization of Fabricated Nanowire Laser Structures

After successfully defending my Master Thesis, I extended my research stay within Prof. Jon Finley’s Chair for Semiconductor Nanostructures and Quantum Systems (E24), Walter Schottky Institute, TUM [1-5],  as a Research Assistant .

I mainly contribute to experimental research efforts connected to Nanowire Lasers, more precisely in the study of embedded multiple quantum well (MQW) structures to shift the lasing peaks towards telecom wavelengths. Our group’s activities around nanowire lasers have been published in several peer-reviewed papers [6-11].

My daily research activities consist of work in several labs and use of advanced state-of-the-art nanofabrication and characterization equipment:
• cleanroom
   – electron beam lithography (eLINE)
   – microscopy (SEM, optical)
   – focused ion beam (FIB)
   – optical lithography
   –  surface profiling
   – spin coating of samples
   – ultrasonic baths
   – work with chemicals
• optics lab
   – photoluminescence (PL) spectroscopy
   – optical setups with lasers, CCD spectrometers, cameras, lenses etc.
   – cryogenics (working with liquid He, cooling of samples)
• numerical simulations
   – Lumerical FDTD (time-domain simulation of propagating optical modes)
   – COMSOL Multiphysics (eigenmode analysis of the nanowire waveguide)
• work on the computer
   – AutoCAD (preparation of masks for lithography)
   – Matlab (results analysis)


[1] Walter Schottky Institute, TUM.

[2] Technical University Munich.

[3] Chair for Semiconductor Nanostructures and Quantum Systems (E24).

[4] Prof. Jonathan J. Finley’s profile on TUM Professors’ website.

[5] Nanowire Group, E24, WSI.

[6] Mayer, B., Janker, L., Loitsch, B., Treu, J., Kostenbader, T., Lichtmannecker, S., Reichert, T., Morkötter, S., Kaniber, M., Abstreiter, G., Gies, C., Koblmüller, G. and Finley, J. (2015). Monolithically Integrated High-β Nanowire Lasers on Silicon. Nano Letters, 16(1), pp.152-156.

[7] Mayer, B., Janker, L., Rudolph, D., Loitsch, B., Kostenbader, T., Abstreiter, G., Koblmüller, G. and Finley, J. (2016). Continuous wave lasing from individual GaAs-AlGaAs core-shell nanowires. Applied Physics Letters, 108(7), p.071107.

[8] Stettner, T., Zimmermann, P., Loitsch, B., Döblinger, M., Regler, A., Mayer, B., Winnerl, J., Matich, S., Riedl, H., Kaniber, M., Abstreiter, G., Koblmüller, G. and Finley, J. (2016). Coaxial GaAs-AlGaAs core-multishell nanowire lasers with epitaxial gain control. Applied Physics Letters, 108(1), p.011108.

[9] Mayer, B., Regler, A., Sterzl, S., Stettner, T., Koblmüller, G., Kaniber, M., Lingnau, B., Lüdge, K. and Finley, J. (2017). Long-term mutual phase locking of picosecond pulse pairs generated by a semiconductor nanowire laser. Nature Communications, 8, p.15521.

[10] Koblmüller, G., Mayer, B., Stettner, T., Abstreiter, G. and Finley, J. (2017). GaAs–AlGaAs core–shell nanowire lasers on silicon: invited review. Semiconductor Science and Technology, 32(5), p.053001.

[11] Stettner, T., Kostenbader, T., Ruhstorfer, D., Bissinger, J., Riedl, H., Kaniber, M., Koblmüller, G. and Finley, J. (2017). Direct Coupling of Coherent Emission from Site-Selectively Grown III–V Nanowire Lasers into Proximal Silicon Waveguides. ACS Photonics, 4(10), pp.2537-2543.