Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.
DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.
The strength of the electron-hole interaction in bulk semiconductors is not only determined by the dielectric environment, but also depends on the presence of other quasiparticles - free charge carriers or phonons - that populate the system. In the former ...
Two-dimensional (2D) materials are atomically thin crystals with exceptional mechanical, electrical and optical properties. Their unique characteristics originating from quantum confinement in the vertical dimension have attracted a strong interest for sci ...
Excitons play an essential role in the optical response of two-dimensional materials. These are bound states showing up in the band gaps of many-body systems and are conceived as quasiparticles formed by an electron and a hole. By performing real-time simu ...
The efficiency and peculiarities of processes such as surface adsorption or electron-to-photon energy conversion in organic and inorganic structures are determined by the dynamics at the scale of individual molecules, atoms and charges. The timescales of s ...
Copper indium sulfide quantum dots (QDs) have attracted substantial attention in recent years due to environmental issues and diverse applications. We report the synthesis and characterization of copper-zinc-indium-sulfide (CZIS) QDs and CZIS treated with ...
Nonradiative recombination in Cu(In,Ga)Se2 (CIGS) solar cells has long been attributed to the antisite defects MCu (M = In, Ga), but the underlying mechanism is still elusive. Using rigorous first-principles calculations, we demonstrate that the antisites ...
In modern ultrafast optoelectronic technologies based on wide band gap insulators, the non-equilibrium dynamics of photogenerated charges plays a major role. Unravelling the mechanisms of interaction between these charge carriers and their environment is c ...
We study the carrier-density-dependent recombination dynamics in m-plane InGaN/GaN multiple quantum wells in the presence of n-type background doping by time-resolved photoluminescence. Based on Fermi's golden rule and Saha's equation, we decompose the rad ...
Since the seminal report about the first Candela-class-brightness InGaN blue light-emitting diodes (LEDs) by Shuji Nakamura et al. in 1994, III-nitride semiconductors have been one of the most important platforms for optoelectronic devices. The achieve ...
Electrical charges can generate photon emission in nanoscale quantum systems by two independent mechanisms. First, radiative recombination of pairs of oppositely charged carriers generates sharp excitonic lines. Second, coupling between currents and collec ...