Latest advances in laser and nanophotonics technology show that a new grade of electronic devices might come. Such devices would operate thousand or million times faster than contemporary computers [1,2]. By exciting charge carriers in the metal-dielectric-metal (or metal-semiconductor-metal) interface using few-cycle laser pulses it is possible to create current pulses with duration on the order of one femtosecond and their direction can be controlled via shaping the laser field. When dealing with few-cycle laser pulses the laser field shape is defined by carrier-envelope phase (CEP). Nowadays the laser technology allows to control the CEP of laser pulses, hence providing a knob to control various physical properties of matter, amongst them the aforementioned ultrafast currents in the dielectrics or semiconductors. Although the relation between the CEP and current direction is already known, the applications of this phenomenon are yet in its beginnings as many questions about its dynamics has not been answered yet. For example the observation of the phenomenon is limited by the slow electronic circuitry, therefore an alternative electronic or a full-optical approach needs to be developed to overcome this limitation. In this work, experiments will be performed that will allow better understanding of the optical current control that will go beyond the limitation of slow electronic circuitry.
The goal of the doctoral training is to execute a state-of-the-art research in the field of optoelectronics and nanoplasmonics. A method will be developed how to measure and manipulate phase relations between electric current in a metal and laser pulse. The method will be based on the non-linear effect obtained in dielectrics (or semiconductors) that allows to generate a phase-sensitive bursts of current in electrodes attached to the dielectric under investigation. Several methods can be used for this purpose, here listing few of them: pump-probe technique, photoelectron spectroscopy from plasmons on nanoparticles, full-optical nonlinear interaction and optoelectronic sampling. The assessment of the appropriate experimental method is the part of the research.
The doctoral candidate would learn operating ultrafast laser technology and will get familiar with fundamental techniques related to them. Amongst them one can name: Frequency resolved optical gating, photoelectron spectroscopy, non-linear optical harmonic generation, pump-probe spectroscopy. The candidate will receive a deeper insight into solid-state physics and microchip technology as she/he is going to propose own optoelectronic components and use techniques to test them. Application and testing of mathematical models goes in hand with the evaluation of the experimental work, therefore the candidate will understand in detail the theoretical aspects of the studied topics as well. Overall, the candidate would have the opportunity to develop and realize own experiments in order to pursuit the set up goals which will lead to her/his independence in research.
1. A. Schiffrin, T. Paasch-Colberg, N. Karpowicz, V. Apalkov, D. Gerster, S. Mühlbrandt, M. Korbman, J. Reichert, M. Schultze, S. Holzner, J. V. Barth, R. Kienberger, R. Ernstorfer, V. S. Yakovlev, M. I. Stockman, and F. Krausz, "Optical-field-induced current in dielectrics," Nature 493, 70–74 (2013).
2. F. Krausz and M. I. Stockman, "Attosecond metrology: from electron capture to future signal processing," Nat. Photonics 8, 205–213 (2014).
University grade training in physics topics. Enthusiasm in physics and science required. Experience with work in a physics laboratory is an advantage, but not required.