Temperature and density dependence of exciton dynamics in IIa diamond: Experimental and theoretical study

Abstract

We studied dependence of time-resolved and time-integrated photoluminescence of free excitons in IIa type monocrystalline diamond on sample temperature and carrier density. Numerical model based on rate equations for time evolution of excited carrier and occupied traps populations was used for theoretical modelling. The density dependent diffusion and free carrier/ free exciton equilibrium were shown to be important factors in exciton recombination dynamics. Room temperature quantum yield of excitonic photoluminescence was found to be strongly dependent on the carrier density with the highest measured value of 13% at n ¼ 10 17 cm À3 .

Computational study of physisorption and chemisorption of polypyrrole on H‐terminated (111) and (100) nanodiamond facets

“…In the 21st century, diamond is investigated owing to its unique semiconducting and chemical properties, e.g., superb hardness, chemical inertness, non‐toxicity, biocompatibility, high carrier mobility, efficient heat dissipation, and luminescence. Diamond has an indirect band structure with the band gap width of 5.5 eV . The applications of diamond are numerous, e.g., in electronics, optoelectronic devices, biosensors, and in photovoltaics.…”

“…Its experimental HOMO–LUMO gap is 1.3–3.2 eV, depending on the method of preparation . There has been an experimental evidence of charge transfer between the bulk diamond and PPy on its surface observed by Kelvin force microscopy and optical spectroscopy .…”

Low-temperature mobility-lifetime product in synthetic diamond

“…Diamond is an attractive material for high-power electronics and photonics owing to its extraordinarily high thermal conductivity, breakdown voltage, and mobility [1][2][3] . In addition, the high radiation hardness and long carrier lifetime 4,5 originating from the indirect bandgap make diamond an ideal material for high-sensitivity radiation detectors. The performance of a diamond radiation detector [6][7][8] depends on both the carrier mobility and lifetime.…”

Features of free carrier and exciton recombination, diffusion, and photoluminescence in undoped and phosphorus-doped diamond layers

“…Using 13% PL efficiency at 10 17 cm -3 carrier density in bulk 0.4 mm thick diamond [3] with R0 = 700 ns [1] bulk lifetime, and the determined B ex and C FC coefficients, exciton radiative lifetime of  REX = 860 ns was obtained. Fit of the experimental PL efficiency in Fig.…”