Related papers: A photoconductor intrinsically has no gain
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…
Although the absorption of light in a bulk homogeneous semiconductor produces photocarriers with non-zero momentum, it generally does not produce a current in the absence of an applied electric field because equal amounts of carriers with…
The absorption of light by free carriers in semiconductors results in optical loss for all photon wavelengths. Since free-carrier absorption competes with optical transitions across the band gap, it also reduces the efficiency of…
The distributed absorption of photons in photodiodes induces an excess noise in continuous-wave photodetection above the transit-time roll-off frequency. We show that it can be treated as a frequency-dependent excess optical loss in…
When light originating from a laser diode driven by non-fluctuating electrical currents is incident on a photo-detector, the photo-current does not fluctuate much. Precisely, this means that the variance of the number of photo-electrons…
The photovoltaic reciprocity theory relates the electroluminescence spectrum of a solar cell under applied bias to the external photovoltaic quantum efficiency of the device as measured at short circuit conditions. Its derivation is based…
Gain in current-driven semiconductor heterostructure devices is calculated within the theory of nonequilibrium Green functions. In order to treat the nonequilibrium distribution self-consistently the full two-time structure of the theory is…
We describe a theory on photo-thermoelectric properties of a semiconductor, which include photo-conductivity, photo-Seebeck coefficient, and photo-Hall effect. We demonstrate that these properties provide a powerful tool for the study of…
The spatial collection efficiency portrays the driving forces and loss mechanisms in photovoltaic and photoelectrochemical devices. It is defined as the fraction of photogenerated charge carriers created at a specific point within the…
Solar cells employing quantum wells can enhance the light absorption but suffer from the difficulty in photogenerated carrier extraction. Here, we analyzed the spectral response and the photocarrier collection mechanism of p-i-n multiple…
Experiments often show that the photoconductance $\sigma$ of a semiconductor system and the light intensity $I$ are related by $\sigma\sim I^\gamma$. Conventional theories give a satisfactory explanation for $\gamma=1$ or $\gamma=1/2$, but…
Photoelectronic properties of Alq3 were studied by photoconductivity measurements in thin film, sandwich (ITO/Alq3/LiF/Al) devices. We find that the photocurrent is dominated by bulk generation of carriers for incident photon energies…
The interplay between the illuminated excitation of carriers and subsequent thermalization and recombination leads to the formation of non-equilibrium distributions for the "hot" carriers and to heating of both electrons, holes and phonons.…
Integrated photonics has undergone tremendous development in the past few decades, transforming many fields of study in science and technology. Loss and gain are two fundamental elements in photonic circuits and have direct impacts on…
Most optical quantum devices require deterministic single-photon emitters. Schemes so far demonstrated in the solid state imply an energy relaxation which tends to spoil the coherent nature of the time evolution, and with it the photon…
The time-of-flight method is a fundamental approach for characterizing the transport properties of semiconductors. Recently, the transient photocurrent and optical absorption kinetics have been simultaneously measured for thin films;…
Photocarrier generation rate in optoelectronic materials is often calculated using the Poynting vector in the frequency domain. However, this approach is not accurate in time-domain simulations of photoconductive devices because the…
Inelastic scattering and carrier capture by defects in semiconductors are the primary causes of hot-electron-mediated degradation of power devices, which holds up their commercial development. At the same time, carrier capture is a major…
Photon condensation in semiconductor microcavities is a transformative technique for engineering quantum states of light at room temperature by tailoring strong but incoherent light-matter interactions. While continuous-wave and electrical…
Thin films are gaining ground in photonics and optoelectronics, promising improvements in their efficiency and functionality as well as decreased material usage as compared to bulk technologies. However, proliferation of thin films would…