Related papers: Dynamic screening of quasiparticles in WS$_2$ mono…
We present a mixed quantum-classical framework for the microscopic and non-Markovian modeling of exciton-phonon scattering in solid-state materials, and apply it to calculate the optical linewidths of monolayer MoS2. Within this framework,…
Strong optical nonlinearities at the few-photon level are a central goal for quantum photonics, yet they remain difficult to realize in solid-state systems. In doped two-dimensional semiconductors, coupling between excitons and a degenerate…
We report magneto-optical spectroscopy of gated monolayer MoS$_2$ in high magnetic fields up to 28T and obtain new insights on the many-body interaction of neutral and charged excitons with the resident charges of distinct spin and valley…
We report an efficient method to observe single photon emissions in monolayer WSe2 by applying hydrostatic pressure. The photoluminescence peaks of typical two-dimensional (2D) excitons show a nearly identical pressure-induced blue-shift,…
Organic semiconducting polymers are currently of broad interest as potential low-cost materials for photovoltaic and light-emitting display applications. I will give an overview of our work in developing a consistent quantum dynamical…
When the energy of a pump wave is in resonance with the exciton creation energy, the electric susceptibility of a conjugated polymer in response to the probe wave is altered by the exciton gas. In this paper, we calculate the dependence of…
The coherent interaction between free electrons and optical fields can produce free-electron compression and push the temporal resolution of ultrafast electron microscopy to the attosecond regime. However, a large electron-light interaction…
A theory is developed for the evolution of the non-equilibrium distribution of quasiparticles when the scattering rate decreases due to particle collisions. We propose a "modified one-collision approximation" which is most effective for…
We studied multi-exciton dynamics in monolayer WSe2 using nonlinear photoluminescence (PL) spectroscopy and Monte Carlo simulations. We observed strong nonlinear saturation behavior of exciton PL with increasing excitation power density,…
Single layers of WS2 are direct gap semiconductors with high photoluminescence (PL) yield holding great promise for emerging applications in optoelectronics. The spatial confinement in a 2D monolayer together with the weak dielectric…
Layered two-dimensional dichalcogenides are potential candidates for post-silicon electronics. Here, we report insightfully experimental and theoretical studies on the fundamental Coulomb screening and scattering effects in these correlated…
Compton scattering is one of the cornerstones of quantum physics, describing the fundamental interaction of a charged particle with photons. The Compton effect and its inverse are utilized in experiments driving free electrons by high…
Coulomb screening, together with degeneracy, is characteristic of the metallic electron gas. While there is little trace of its effects in transport and noise in the bulk, at mesoscopic scales the electronic fluctuations start to show…
Recent ultrafast optical experiments show that excitons in large biological light-harvesting complexes are coupled to molecular vibration modes. These high-frequency vibrations will not only affect the optical response, but also drive the…
Enhanced Coulomb interactions in monolayer transition metal dichalcogenides cause tightly bound electron-hole pairs (excitons) which dominate their linear and nonlinear optical response. The latter includes bleaching, energy…
Monolayers of transition metal dichalcogenides present an intriguing platform to investigate the interplay of excitonic complexes in two dimensional semiconductors. Here, we use optical spectroscopy to study light-matter coupling and…
A quantum behavior of the light emitted by exciton polaritons excited in a pillar semiconductor microcavity with embedded quantum well is investigated. Considering the bare excitons and photon modes as coupled quantum oscillators allows for…
Van der Waals heterostructures usually formed using atomic thin transition metal dichalcogenides (TMDCs) with a direct bandgap in the near-infrared to the visible range are promising candidates for low-dimensional optoelectronic…
Coulomb bound electron-hole pairs, excitons, govern the optical properties of semi-conducting transition metal dichalcogenides like MoS$_2$ and WSe$_2$. We study optical transitions at the K-point for 2H homobilayer MoS$_2$ in Density…
In the cuprates, the opening of a d-wave superconducting (SC) gap is accompanied by a redistribution of spectral weight at energies two orders of magnitude larger than this gap. This indicates the importance to the pairing mechanism of…