Terahertz goes nano
A joint team of the Nanooptics Laboratory at nanoGUNE and the Nanophotonics Group at the Max-Planck-Institute of Biochemistry (Germany), in collaboration with the DIPC – CSIC UPV/EHU and Infineon Technologies AG (Munich), has recently achieved nanoscale resolved imaging in the terahertz (THz) frequency range (wavelengths between 30 and 1000 μm) by the use of near-field microscopy.
Illuminating the sample with THz radiation of 118 μm (2,5 THz) they have been able to resolve details as small as 40 nm (0,04 μm). Therefore, this THz microscope breaks the diffraction barrier by a factor of 1500. The THz near-field microscopy does not only allow for nanoscale imaging of materials, but it can be also used for recognition of mobile carriers in semiconductor nanodevices. This opens the door to quantitative studies of local carrier concentration and mobility at the nanometer scale. Hitherto, no powerful metrology tools are available allowing for simultaneous and quantitative mapping of both materials and carrier concentrations with nanoscale resolution. The added values of seeing and even quantifying conducting carriers opens an enormous industrial application potential for the THz near-field microscope. Future improvements could allow for THz characterization of even single electrons or biomolecules. The results have been published today in Nanoletters.
Dr. Rainer Hillenbrand, email@example.com.