Title
Design and fabrication of mid-IR plasmonic materials based on highly doped III-V semiconductors
Supervisors
Principal supervisor: Assoc. Professor Andrei Lavrinenko, DTU Fotonik
Co-supervisor: Dr. Elizaveta Semenova, DTU Fotonik
Evaluation Board
Assoc. Professor Kresten Yvind, DTU Fotonik
Professor Nader Engheta, University of Pennsylvania, USA
Assoc. Professor Vladimir Bordo, SDU NanoSyd, Denmark
Master of the Ceremony
Assis. Professor Nicolas Stenger, DTU Fotonik
Abstract
Plasmonics is one of the important and emerging fields in photonics, with applications such as plasmon-enhanced photovoltaics, sensing, Raman spectroscopy and subwavelength waveguiding. Noble metals such as gold and silver are considered as traditional plasmonic materials for the visible range, due to their abundant free electrons, but they suffer from high losses in the infrared range. In this project silicon doped InP is studied as an alternative low loss plasmonic material for the mid-infrared wavelength range. InP:Si films are grown using MOVPE and the effect of the growth conditions on the electrical and optical properties of InP:Si is studied. Using the experimentally determined dielectric function, surface plasmon polaritons on the surface of InP:Si are simulated and observed in direct experiments. Good agreement between the theory and the experimental results confirms that highly doped InP is an effective plasmonic material aiming it for applications in the mid-infrared wavelength range. Comparison to other semiconductors shows superior plasmonic performance in terms of the propagation length and confinement. In order to demonstrate one of the novel applications of semiconductors in the mid-infrared range, enhanced optical forces in InP-based waveguides are investigated which can be utilized as a novel actuation method for MEMS devices.