Condensed Matter Theory
Thermal imaging at the nanoscale
We develop a theoretical description of the heat flux between a miniaturized sensing tip and a structured surface of different temperature at nanometer distances. A nearfield effect known as “photon tunneling” then allows one to obtain images of the surface. Because such a “photon tunneling microscope” is sensitive to the electromagnetic local density of states, the information acquired in this manner differs from that accessible to a conventional electron tunneling microscope, which maps the electronic local density of states.This work is performed in close collaboration with the experimental Energy and Semiconductor Research Group headed by Jürgen Parisi. Under the guidance of Achim Kittel, this group has developed a functioning NearField Scanning Thermal Microscope (NSThM), which has the unique capability of assessing the extreme nearfield regime. Our joint Oldenburg Project aims at a comprehensive understanding of the working principles of this novel instrument. The figures below show a theoretically reconstructed (left) and an experimentally measured (right) thermal image of a nanostructured surface.
 Achim Kittel, Wolfgang MüllerHirsch, Jürgen Parisi, SvendAge Biehs, Daniel Reddig,
and Martin Holthaus:
NearField Heat Transfer in a ScanningThermal Microscope.
Phys. Rev. Lett. 95, 224301 (2005).
arXiv:1103.3278v1

SvendAge Biehs, Oliver Huth, and Felix Rüting:
Nearfield radiative heat transfer for structured surfaces.
Phys. Rev. B 78, 085414 (2008).
arXiv:1103.3050v1

Achim Kittel, Uli Wischnath, Joachim Welker, Oliver Huth, Felix Rüting, and SvendAge Biehs:
Nearfield thermal imaging of nanostructured surfaces.
Appl. Phys. Lett. 93, 193109 (2008).
Also selected editorially for the November 24, 2008 issue of the Virtual Journal of Nanoscale Science & Technology.
arXiv:1103.3059v2

SvendAge Biehs, Oliver Huth, Felix Rüting and Martin Holthaus:
Spheroidal nanoparticles as thermal nearfield sensors.
J. Appl. Phys. 108, 014312 (2010).
arXiv:1103.4511v1

Felix Rüting, SvendAge Biehs, Oliver Huth, and Martin Holthaus:
Secondorder calculation of the local density of states above a nanostructured surface.
Phys. Rev. B 82, 115443 (2010).
arXiv:1103.3221v1
Disclaimer Druckversion SvendAge Biehs; Last modified: Dec 19 2011