INT | Research Unit Krupke

Research

Research Highlights

Our research focus is on carbon nanotubes and graphene, which we integrate into device structures to explore their potential for high-speed electronics, optoelectronics, and sensing, and to perform fundamental science experiments. Here are some of the highlights of our research. You can find a lot more on our publications page.

Low-Temperature Electroluminescence of Excitons and Trions in Monochiral Carbon Nanotube Devices
Low-temperature Electroluminescence spectroscopy of ultra-short-channel devices made from (9,8) carbon nanotubes emitting in the telecom band were repoted with line widths down to 2 meV at 4 K. 

ACS Nano (2020) DOI:10.1021/acsnano.9b07207

Krupke

Towards on-chip communication with carbon nanotubes
Electrically driven nanotubes can be forced to emit light with a specific color by integration into photonic crystal waveguide.
Nature Photonics (2016) DOI:10.1038/nphoton.2016.70

Krupke

Carbon nanotubes for high-density short-channel transistors
Best performing short-channel transistors have been built by using highly enriched semiconducting single-wall CNs prepared by combining polymer-wrapping with size-exclusion chromatography.

ACS Nano 10(2) (2016) 1888

Krupke

Photocurrent Spectroscopy of Solution Processed SWCNTs
We demonstrate the use of variable-wavelength photocurrent microscopy and photocurrent spectroscopy to study the photoresponse of (n, m) sorted SWNT devices.

ACS Nano (2014) DOI:10.1021/nn503278d

Krupke

Waveguide-coupled light sources 
Light from an electrically driven carbon nanotube has been coupled directly into a photonic waveguide structure.
Advanced Materials 26 (2014) 3465

Krupke

Maskless lithography of graphene
Electron-beam-induced oxidation is used to write arbitrary patterns into graphene.
Carbon 64 (2013) 84-91

Krupke

Alcohol helps to sort CNTs
Near monochiral s-SWCNT fractions are prepared with a simple, high-throughput procedure based on the introduction of 1-dodecanol to a chromatography column.
ACS Nano 7 (2013) 3557-3564

The role of Nanotubes in CNT-Si Solar Cells
We discuss the role of CNTs in typical CNT-Si solar cell designs.
Advanced Energy Materials (2013)

Krupke

Nanoparticles digging the world's smallest tunnels
Nickel nanoparticles are used to etch world's smallest tunnels into graphite.

[Nanowerk] [F.A.Z.]
Nature Communications 4 (2012) 1379

Krupke

153 GHz CNT FET
We demonstrate a record-breaking 153 GHz carbon nanotube transistor.
Appl. Phys. Lett. 101 (2012) 053123

Krupke

Graphene in a cavity
A sheet of graphene inside an optical cavity shows spectrally confined thermal emission.

[KIT press]  [Physik in unserer Zeit]
Nature Communications 3 (2012) 906

Molecular flashlight
We observe electroluminescence from a single nanotube-molecule-nanotube junction.

[F.A.Z.] [Nanowerk] [KIT Video]
Nature Nanotechnology 5 (2010) 863

Krupke

CMOS-compatible assembly of nanotube devices
High-density arrays of semiconducting carbon nanotube devices are fabricated in a CMOS-compatible process.

[Nanowerk]
Advanced Materials 23 (2011) 1734

Krupke

Voltage-Contrast imaging of carbon nanotubes
The electronic structure of carbon nanotubes is revealed in-situ in a scanning electron microscope using voltage-contrast imaging.
Nano Research 1 (2008) 321-332

Krupke

Separation of Metallic from Semiconducting Single-Walled Carbon Nanotubes
Using AC-dielectrophoresis a separation of metallic and semiconducting nanotubes was achieved.
Science 18 (2003) 344-347