Diese Arbeit untersucht die optischen Eigenschaften von Übergangsmetall-Dichalkogenid (engl. transition metal dichalcogenide; TMD)-Monolagen. Diese ultradünnen Halbleiter eignen sich aufgrund ihrer einfachen Integration in bestehende photonische Plattformen, ihrer breitbandigen Anwendbarkeit, ihrer starken…
Abstract Two-dimensional (2D) semiconductors are emerging as a versatile platform for nanophotonics, offering unprecedented tunability in optical properties through exciton resonance engineering, van der Waals heterostructuring, and external field control. These materials enable active optical modulation,…
Abstract Transition metal dichalcogenide (TMD) alloys provide a stable and reliable platform for broadband tuning of excitonic resonances. Here, the nonlinear optical response of Mo (1 − x) W x Se 2 , focusing in particular on second harmonic generation (SHG) and two‐photon photoluminescence (TP‐PL),…
Monolayer transition metal dichalcogenides (TMDs) are direct gap semiconductors where the optical properties are dominated by strongly interacting electron–hole quasi-particles. Understanding the interactions among these quasi-particles is crucial for advancing optoelectronic applications. Here, we examine…
Washington, DC: American Chemical Society, 2025-05-15
Fluoreszenzmikroskopie ist ein wichtiges Instrument in der Material- und biomedizinischen Forschung. Dabei wurden spezialisierte bildgebende Verfahren für unterschiedliche Fragestellungen entwickelt. Jedes fluoreszenzmikroskopische Verfahren bietet eigene Vorteile, etwa ein hohes axiales und laterales…
Abstract Graphene is a unique platform for tunable opto‐electronic applications thanks to its linear band dispersion, which allows electrical control of resonant light‐matter interactions. Tuning the nonlinear optical response of graphene is possible both electrically and in an all‐optical fashion, but…
The rapid advancement of technology demands innovative materials and scalable fabrication methods for faster data transport and miniaturized devices. Transition metal dichalcogenides (TMDs), with exceptional optoelectronic properties, show promise for hybrid photonic nanostructures. However, current…
This Ph.D. thesis is primarily focused on the growth, device fabrication, and characterization of organic and inorganic materials and their heterostructures, with the objective of exploring their unique properties. The scope of this work encompasses the fabrication of various devices, including ambipolar…
Thanks to their long lifetime, spin-forbidden dark excitons in transition metal dichalcogenides are promising candidates for storage applications in opto-electronics and valleytronics. To date, their study has been hindered by inefficient generation mechanisms and the necessity for elaborate detection…
Abstract Janus transition metal dichalcogenides are an emerging class of atomically thin materials with engineered broken mirror symmetry that gives rise to long‐lived dipolar excitons, Rashba splitting, and topologically protected solitons. They hold great promise as a versatile nonlinear optical platform…
Abstract With conventional electronics reaching performance and size boundaries, all‐optical processes have emerged as ideal building blocks for high speed and low power consumption devices. A promising approach in this direction is provided by valleytronics in atomically thin semiconductors, where light‐matter…
Light sources with specific optical properties are the backbone of optical technologies such as spectroscopy or hyperspectral imaging. Yet, the creation of broadband, stable, and spectrally flat light sources, especially at low pump energies, remains a particular challenge. Supercontinuum generation…
The work presented in this dissertation is dedicated to the characterization of the excited state dynamics of thin films through time-resolved spectroscopy, with emphasis on developing a methodology that is able to resolve weak transient absorption signals from optically thin films. With this aim, the…
Optical‐microcavity‐enhanced light–matter interaction offers a powerful tool to develop fast and precise sensing techniques, spurring applications in the detection of biochemical targets ranging from cells, nanoparticles, and large molecules. However, the intrinsic inertness of such pristine microresonators…
Nonlinear optics is of crucial importance in several fields of science and technology with applications in frequency conversion, entangled‐photon generation, self‐referencing of frequency combs, crystal characterization, sensing, and ultra‐short light pulse generation and characterization. In recent…
Die mit dem technischen Fortschritt eng verbundene Miniaturisierung von elektronischen Bauteilen wird durch Quanteneffekte im Nanometerbereich begrenzt, sodass die konventionelle Halbleitertechnologie in naher Zukunft an ihre physikalischen Grenzen stößt. Als technologische Alternative scheinen Hybridsysteme…
Abstract Soliton frequency combs generate equally-distant frequencies, offering a powerful tool for fast and accurate measurements over broad spectral ranges. The generation of solitons in microresonators can further improve the compactness of comb sources. However the geometry and the material’s inertness…
In dieser Arbeit werden extreme nichtlineare optische Phänomene in hoch angeregten ZnO Halbleiterproben untersucht. ZnO hat eine Bandlücke von 3,2 eV im nahen ultravioletten Spektralbereich und die optische Anregung erfolgt mit starken Lichtfeldern im nahen bis fernen nfrarot. Folglich ist die Energie…