Ulf Peschel is chairholder at the Institute of Solid State Theory and Optics, a Senior Fellow of the Optical Society of America, a member of the Coucil of the Abbe School of Photonics, and Spokesperson of the cooperative research center SFB 1375 „Nonlinear Optics down to Atomic scales (NOA)“.
Some of Ulf Peschel's current research activities focus on the time evolution of optical pulses in fiber systems. Together with his group "Nonlinear Optics and Nanophotonics (NONA)" and for the first time, he realized a discrete system in the time domain and investigated time discrete temporal solitons. He currently studies optical systems with balanced gain and loss, which may allow for the formation of fractal patterns and if they obey parity-time (PT) symmetry also for sudden phase transitions and unidirectional invisibility. Recently, the group observed the first PT-symmetric optical solitons. Ulf Peschel's research in the field of nanophotonics is concentrated on metamaterials, photonic crystals and plasmonic structures. Together with his co-workers he developed new methods to characterize highly focused beams and explored the optical response of dielectric-plasmonic crystals. For the first time, his group realized the excitation of sub-wavelength plasmonic gap-waveguides and of plasmonic nano-circuitries via nanoantennas. Modelling activities focus on the efficient implementation of codes simulating light-matter interaction in semiconductor nanostructures based on finite-difference time domain (FDTD) codes coupled with semiconductor Maxwell-Bloch equations.