He developed several precision instruments, e.g. for
synchrotron radiation sources, helium lamps for UV and
angle-resolved photoemission spectroscopy (ARPES), and he used these to study high-temperature superconductors. For example, his group in 2010 obtained convincing evidence that the
pseudogap phase of the cuprate high-temperature superconductors, which was discovered in the mid 1990s, indeed is an independent phase (independent from the metallic and superconducting phases), which reaches into the superconducting phase. Besides ARPES techniques in the UV regime, he also employs x-ray diffraction methods. He developed near-field microwave microscopy (scanning microwave impedance microscopy) based on
atomic force microscopes for studies on mesoscopic length scales, e.g. nanostructured materials. Using this, he addresses applications such as new techniques for solar collectors (Photo Enhanced Thermionic Emission, PETE). ==Awards==