I am a PhD student in the science group Complex Materials and Devices. Originally I am from Lycksele (Sweden) but I did my studies in Applied Physics and Electrical Engineering, with specialization in Nano and Material Physics, here at Linköping University. In the CoMaDe group I am investigating ratchet structures for potential use in energy harvesting.


On/off ratchets

 

Figur 1The most common type of ratchet is an on/off ratchet which generates a sawtooth potential in its “on”-state and a flat potential in its “off”-state. Here, the idea is that particles are localized in the potential wells when the potential is on. When the potential is off, the particles will diffuse and spread over a wider area. Consequently, when the potential is turned on again, re-forming the sawtooth potential, the particles that had diffused over an edge will drift to the bottom of the re-formed well. Because of the asymmetric shape of these wells, a net motion is achieved by periodically turning on and off the potentials. [1]

Rectification of electromagnetic radiation

Figur 2

An example of a non-directional perturbation is an alternating electric field; rectification of this might find use in e.g. novel RF antennas. When we subject charges (electrons or holes) that sit in a periodic asymmetric channel, i.e. a ratchet, the asymmetry will result in a net DC current that can power electric circuitry. The effect can be investigated for materials with different mobility and the charge carrier densities can be controlled via doping and/or a gate field in a so-called field effect transistor.

[1] Appl. Phys. Lett. 102, 073104 (2013) doi: 10.1063/1.4793198

Publications

2018

Guangzheng Zuo, Olof Andersson, Hassan Abdalla, Martijn Kemerink

High thermoelectric power factor from multilayer solution-processed organic films

In Applied Physics Letters

Article in journal

2017

Guangzheng Zuo, Zhaojun Li, Olof Andersson, Hassan Abdalla, Ergang Wang, Martijn Kemerink

Molecular Doping and Trap Filling in Organic Semiconductor Host-Guest Systems

In The Journal of Physical Chemistry C

Article in journal

2015

Jonas Bergqvist, Armantas Melianas, Olof Andersson, Camilla Lindqvist, Chiara Musumeci, Olle Inganäs

Time-resolved morphology formation of solution cast polymer: fullerene blends revealed by in-situ photoluminescence spectroscopy

Manuscript (preprint)