Terahertz Photoconductivity

Tailoring Ultrafast Near-Band Gap Photoconductive Response in GeS by Zero-Valent Cu Intercalation

“…We present the spectra as average film conductance, a product of conductivity σ, and (unknown) average thickness. Given the relatively large lateral dimensions of the nanoribbons (Figure 1b), and despite the inherent disorder of the nanoribbon ensembles, we find that the complex conductivity spectra are well-described by the Drude model, which is often applied to describe THz conductivity of free carriers in bulk materials 31,55 :…”

UV-excited single-component white phosphor of Lu2WO6 with broad-band emission for pc-WLED

“…Exciton binding energy ( E b ) is the energy difference between a bound electron–hole pair and a pair of free electrons and holes. Usually, the exciton binding energy ( E b ) can be estimated as follows: 32,33 E b = μ * R y / m 0 ε r 2 ,where μ is the reduced effective mass. R y is the atomic Rydberg energy, m 0 is the electron rest mass, and ε r is the relative dielectric constant.…”

“…S3 † illustrates the density of the state of the three lutetium tungstates.Exciton binding energy (E b ) is the energy difference between a bound electron-hole pair and a pair of free electrons and holes. Usually, the exciton binding energy (E b ) can be estimated as follows:32,33…”

Tailoring ultrafast photoconductive response in GeS and GeSe by zero-valent Cu intercalation

“…THz probe pulses with the energy bandwidth in ~ 2-8 meV are uniquely sensitive to the free charge carriers, thus allowing us to monitor transient photoconductivity and determine the lifetimes of optically excited carriers. 18 We demonstrate that relatively low zerovalent Cu concentration of ~ 3% has a profound effect on response of GeS and GeSe multilayer nanoribbons to near excitation with 1.55 eV pulses, shortening the photoconductivity rise time and reducing the lifetime of optically injected charge carriers.…”

“…Complex frequency-resolved photoconductivity at a fixed time after excitation can be calculated by the Tinkham equation, analyzing the change to the THz pulse due to the photoexcitation. 18…”