Technische Universität München
Lehrstuhl für Nanotechnologie und -materialien (Prof. Holleitner)
Am Coulombwall 4
85748 Garching b. München
The Holleitner group investigates optoelectronic phenomena in nanoscale circuits with special focus on ultrafast optoelectronics, quantum optoelectronics, and excitonic systems. Exploiting an on-chip THz time-domain photocurrent spectroscopy, picosecond currents in na-noscale circuits are explored in the time domain including dielectric displacement currents, the non-equilibrium transport of photogenerated charge and spin carriers, helicity dependent currents, time-resolved photo-thermoelectric phenomena, and recombination lifetime limited photocurrents. A further topic is the study of many-body phenomena and interactions in dipolar excitonic ensembles in nanofabricated quantum traps formed in semiconductor heterostructures. In addition, novel types of photo-electronic systems are constructed and investigated that consist of mixed organic and inorganic nanosystems such as molecules, nanocrystals, 2D layered materials, carbon nanotubes, and photosynthetic "light harvesting" proteins. The research topics aim to fully exploit the potential of nanoscale circuits for optoelectronic and photovoltaic applications, as well as for communication and information technologies.
Beilstein Journal of Nanotechnology
Abstract: Compared to bulk solids, defects in low-dimensional materials and, specifically, 2D systems are expected to have a stronger effect, detrimental or beneficial, on their properties. Owing to their…
Advanced Quantum Technologies
Abstract: We explore the zero-phonon line of single photon emitters in helium-ion treated monolayer MoS2, which are currently understood in terms of single sulfur-site vacancies. By comparing the linewidths of…
ACS Applied Optical Materials
Abstract: We demonstrate the in situ readout of the spatial profile of suspended MoS2 monolayers hosted on substrates with nanostructured holes. As the profiles are spatially bent, the suspended MoS2 monolayers…
Physical Review Materials
Abstract: We explore the optical dipole orientation of single photon emitters in monolayer MoS2 as produced by a focused helium ion beam. The single photon emitters can be understood as single-sulfur vacancies.…
2D Materials
Abstract: We investigate the interplay between vertical tunneling and lateral transport phenomena in electrically contacted van der Waals heterostructures made from monolayer MoS2, hBN, and graphene. We compare…
Scientific Reports
Abstract: Polarized optical contrast spectroscopy is a simple and non-destructive approach to characterize the crystalline anisotropy and orientation of two-dimensional materials. Here, we develop a 3D-printed…
Physical Review Materials
Abstract: Hexagonal boron nitride (hBN) hosts luminescent defects possessing spin qualities compatible with quantum sensing protocols at room temperature. Vacancies, in particular, are readily obtained via…
Applied Physics Reviews
Abstract: We highlight recent advances in the controlled creation of single-photon emitters in van der Waals materials and in the understanding of their atomistic origin. We focus on quantum emitters created in…
Advanced Materials
Abstract: Strain engineering promises to enable manipulation and control of the properties of exfoliated flakes of 2D van der Waals (vdW) ferromagnets for spintronic applications. However, while previous…
npj Quantum Materials
Abstract: Heterostructures made from 2D transition-metal dichalcogenides are known as ideal platforms to explore excitonic phenomena ranging from correlated moiré excitons to degenerate interlayer exciton…
