Ultrafast Nanoscale Optoelectronics




Exploiting an on-chip laser pump/probe spectroscopy, we experimentally investigate picosecond photocurrents in nanoscale circuits in the time domain including dielectric displacement currents, the transport of photogenerated charge carriers to the contacts, time-resolved photo-thermoelectric phenomena, and recombination lifetime limited photocurrents.


Video: Time-resolved picosecond photocurrents in graphene


Recent Highlights 

Graphene layer reads optical information from nanodiamonds electronically

In a recent publication in Nature Nanotechnology, we demonstrate that the spin of nitrogen-vacancy centers in diamond can be electronically read-out using a graphene layer on a picosecond time-scale. Nitrogen-vacancy centers in diamonds could be used to construct vital components for quantum computers. But hitherto it has been impossible to read optically written information from such systems electronically. The work was led by the group of Alexander Holleitner in collaboration with Frank Koppens (ICFO, Barcelona).

Ultrafast photodetection in the quantum wells of single AlGa/AsGaAs-based nanowires

Ultrafast electronic readout of diamond nitrogen-vacancy centres coupled to graphene

Optical control of internal electric fields in band-gap graded InGaN nanowires

Time-resolved picosecond photocurrents in contacted carbon nanotubes

Time-resolved ultrafast photocurrents and terahertz generation in freely suspended graphene

Ultrafast photo-thermoelectric and transport currents in GaAs nanowires

Ultrafast photocurrents and THz generation in single InAs-nanowires

Sub-diffraction optical coherent control of ultrafast electrical currents in antenna devices on GaAs



Heike Riel (IBM), Anna Fontcuberta i Morral (Lausanne, Switzerland), Li Song (USTC Hefei, China), Pulickel Ayajan (Rice, USA), Dieter Schuh (Regensburg, Germany), Helmut Karl (Augsburg, Germany), Werner Wegscheider (Zurich, Switzerland), Frank Koppens (ICFO, Barcelona, Spain)


Recent Publications

A list of recent publications can be found here.



Funding by the following institutions is gratefully acknowledged: 

Nanosystems Initiative Munich

ERC consolidator grant: NanoREAL (No. 306754)

TUM Technische Universität München TUM Technische Universität München Physik Department Elektrotechnik und Informationstechnik TUM Technische Universität München