Related papers: Surface properties of semiconductors from post-ill…
Radiative and non-radiative charge carrier recombination in thin-film diodes plays a key role in determining the efficiency of electronic devices made of next generation semiconductors such as organic, perovskite and nanocrystals. In this…
Electrical transients enabled by optical excitation and electric detection provide a distinctive opportunity to study the charge transport, recombination and even the hysteresis of a solar cell in a much wider time window ranging from…
We present photoluminescence studies as a function of temperature from a series of conjugated polymers and a conjugated molecule with distinctly different backbone conformations. The organic materials investigated here are: planar…
Photocurrent spectroscopy is a versatile technique to identify and understand the optoelectronic dynamics occurring in semiconductor nanowires. Conventional photocurrent spectroscopy allows to explore the morphology and material properties…
Franz-Keldysh effect is expressed in the smearing of the absorption edge in semiconductors under high electric fields. While Franz and Keldysh considered a limited case of externally applied uniform electric field, the same effect may be…
A scattering method is used to calculate the surface band structure of Al(111) from 8.6 eV below the Fermi level to 9 eV above it. This method has rarely been implemented previously. The complete complex bulk and surface band structure is…
This paper models light scattering through flat surfaces with finite transmission, reflection and absorption rates, with wave packets approaching the mirror from both sides. While using the same notion of photons as in free space, our model…
The effect of screening of the coulomb interaction between two layers of two-dimensional electrons, such as in graphene, by a highly doped semiconducting substrate is investigated. We employ the random-phase approximation to calculate the…
Time-dependent current of the electrons excited in the conduction band after ultrafast interband photogeneration is studied theoretically. The transient photocurrent is calculated for the nonlinear regime of response to a stationary…
Logarithmic voltage profile characteristic to two-dimensional current flows has been reported for several semiconductor surfaces. We analyse this phenomenon within a simple model of accumulation and inversion layers. Prompted by numerical…
Photoconductors based on semiconducting thin films, nanowires and 2-dimensional atomic layers have been extensively investigated. But there is no explicit photogain equation that allows for fitting and designing photoresponses of these…
In this work, we approximate the surface photovoltage (SPV) transients in nm-sized ZnO films by the equivalent RC circuit model. The SPV rises in time in time for about 90 mcs after the exciting light pulse at 275 nm is off at different…
An algorithm is introduced for using electrical surface measurements to detect and monitor cracks inside a two-dimensional conductive body. The technique is based on transforming the probing functions of the classical enclosure method by…
In the present work, a light-controlled device cell is established based on the dye-sensitized solar cell using nanocrystalline TiO2 films. Voltage-current curves are characterized by three types of transport behaviors: linear increase,…
In this work, we use pump-probe Kelvin Probe Force Microscopy (pp-KPFM) to investigate light-induced surface potential dynamics in alumina-passivated crystalline silicon, and in an organic bulk heterojunction thin film based on the…
We compute the transient dynamics of phonons in contact with high energy "hot" charge carriers in 12 polar and non-polar semiconductors, using a first-principles Boltzmann transport framework. For most materials, we find that the decay in…
Identification of charge carrier separation processes in perovskite/silicon tandem solar cells and recombination at buried interfaces of charge selective contacts is crucial for photovoltaic research. Here, intensity- and wavelength-…
Metadevices based on dielectric nanostructured surfaces with both electric and magnetic Mie-type resonances have resulted in the best efficiency to date for functional flat optics with only one disadvantage: a narrow operational bandwidth.…
In the previous studies, the ultraviolet light thermoreflectance (UV-TDTR) signal from bulk semiconducting samples cannot be well explained by a thermal models based on the assumption that the heat is both absorbed and probed near the…
Surface resonance states are electronic states localized near the surface while remaining hybridized with bulk bands. These states can strongly modify the electric-field response of semiconductors. Here, we demonstrate using scanning…