We use the nearfield of plasmonic nanostructures to control the excited state dynamics of excitonic materials such as semiconductor nanoplatelets, nanocrystals and molecules.
The central idea is to shape the nearfield in space and time to act as a well-controlled nano-environment.
We combine nanofabrication, including controlled placement of emitters, with ultrafast external fields, optical spectroscopy and nearfield microscopy.
Terahertz-electric field control of exciton dynamics down to the single nanocrystal
Supervisor: G. Herink, Experimental Physics, UBT
Strong Terahertz fields offer novel strategies to probe and tailor exciton dynamics on ultrafast timescales.
In this project, we will explore the control of exciton photophysics via THz-nearfields, enabling the fast switching of optoelectronic function inside nanostructures and applications for nanoscale sensing.
The project builds on ultrafast spectroscopy infrastructure in Bayreuth and includes nanostructure assembly and characterization in Melbourne.
The ideal candidate should have experience in ultrafast optics and laser spectroscopy and be highly motivated to advance his/her knowledge in an interdisciplinary environment.
Ultrafast spectroscopy of coupled quantum emitters
Supervisor: M. Lippitz, Experimental Physics, UBT
An especially intriguing effect of nanostructure-modified emission and absorption processes is the channelling of one photon emitted by one quantum emitter to a second remote emitter and let it absorb there.
When the absorption probability approaches one, the second quantum emitter acts as an optical transistor.
Ultimately, when the photon exchange rate is large enough, both emitters would couple coherently and form a state similar to a molecular J-aggregate.
We plan to position two nanocrystals near a plasmonic waveguide (in Melbourne) and study their incoherent and coherent interaction by ultrafast spectroscopy of single emitters (in Bayreuth) and by nearfield microscopy (in Melbourne)
The ideal candidate should have a background in optics and spectroscopy to set up and run spectroscopic experiments.
Nearfield imaging of hybrid plasmonic nanostructures
Supervisor: A. Funston, Chemistry, MON
Co-supervisor: G. Herink, Experimental Physics, UBT; M. Lippitz, Experimental Physics, UBT; P. Mulvaney, Chemistry, UoM
A challenge in the translation of nanoscale objects to larger, functional structures is the precise placement of the nanoscale objects in an ideal geometry with respect to one another.
This project will extend nanoparticle self-assembly techniques to achieve the specific placement of asymmetric nanoparticles in a well-defined geometry with respect to one another.
This ability is key to manipulating the optical response of nanostructures in a predictable and useful way.
The photoluminescence and near-field of the resultant structures will be interrogated using single particle/assembly optical microscopy and scanning near-field optical microscopy.