Development of a THz Near-Field Nanomicroscope with Nanometer Resolution
Professor Hae-Wook Han's Electrical Engineering team plans future technology transfer to related companies.
Research on THz nanodevices based on quantum materials such as graphene and topological insulators, and THz bionanodevices based on DNA and proteins, has recently drawn considerable attention. Researchers in the United States, Europe, and Japan, including the Max Planck Institute, have worked to develop technology that directly measures theoretically predicted THz nanostructure properties and fabricated device characteristics, but satisfactory results have remained elusive.
After years of effort to address this challenge, Professor Han's team at POSTECH's Department of Electrical Engineering realized the world's first THz near-field nanomicroscope capable of observing broadband spectroscopic characteristics of nanostructures at nanometer resolution. The results were published in ACS Nano Letters, a leading journal in nanodevices and nanomaterials.
The fundamental obstacle has been the strong diffraction caused by the long THz wavelength of about 300 μm. Since conventional technology could not overcome this diffraction limit, the team developed an original technique for which overseas patent applications have already been filed. The resulting ultrabroadband THz nanoimaging technology achieves 90 nm resolution, approximately 1/3,300 of the wavelength, while obtaining spectroscopic information across 0.1–2 THz. This is a remarkable achievement compared with commercial infrared near-field microscopes, whose resolution is about one-tenth of the wavelength.
Principal investigator Professor Han said, “This achievement is only the beginning. It will make a decisive contribution to advancing nanomaterial and nanodevice research in various fields. We plan to pursue joint research with prominent overseas researchers and technology transfer agreements with relevant companies soon.”
Paper: http://pubs.acs.org/doi/abs/10.1021/nl503998v
