A5041714953- GaN-based semiconductor devices and materials
- Semiconductor Quantum Structures and Devices
- ZnO doping and properties
- Ga2O3 and related materials
- Semiconductor materials and devices
- High-pressure geophysics and materials
- Gas Sensing Nanomaterials and Sensors
- Advanced Semiconductor Detectors and Materials
- Acoustic Wave Resonator Technologies
- Nanowire Synthesis and Applications
- Perovskite Materials and Applications
- Metal and Thin Film Mechanics
- Chalcogenide Semiconductor Thin Films
- Optical properties and cooling technologies in crystalline materials
- Radiation Detection and Scintillator Technologies
Vilnius University
2015-2025
The generation and transport parameters of charge carriers are critical for the evaluation optoelectronic devices. In this study, we alloyed CsPbI3 perovskite by partially substituting Pb2+ with Zn2+ in a simple solution process technique. spin-coated thin films were investigated to analyze effect substitution on carrier lifetimes diffusion coefficients. Samples moderate levels Zn exhibited improved morphological characteristics higher absorption coefficient. No significant band gap shift...
<title>Abstract</title> To improve the emission efficiency of InGaN/GaN multiple quantum wells (MQWs), we used high indium content short-period superlattice (SPSL) underlayer and validated approach by studying structural optical properties. The SPSL underlayers were deposited at temperatures equal to or below growth temperature active region MQWs. impact such was studied using XRD, photoluminescence (PL), light-induced transient grating (LITG) techniques. large redshift PL band higher low...
Spectrally and spatially‐resolved nonlinear optical techniques were combined with the photoluminescence spectroscopy to study carrier dynamics efficiency in highly excited blue‐ green‐emitting InGaN/GaN quantum wells. The differential transmission transient grating provided lifetimes diffusivity extended states energies above emission band revealed their dependences on excess density. At high excitation conditions, an increase of led nonradiative recombination rate, being more pronounced...
The diffusion coefficient of holes can provide knowledge about carrier localization in ($\mathrm{In}$,$\mathrm{Ga}$)$\mathrm{N}$, where the dynamics are altered by randomly fluctuating potential landscape. In group-III nitrides, diffusivity is difficult to measure electrical methods but it be studied using optical techniques. Here, we investigate dependence hole on direction and density $c$-plane $m$-plane ($\mathrm{In}$,$\mathrm{Ga}$)$\mathrm{N}$ structures employing light-induced...
Indium nitride has a good potential for infrared optoelectronics, yet it suffers from fast nonradiative recombination, the true origin of which not been established with certainty. The diffusion length free carriers at high densities is well investigated either. Here, we study carrier recombination and using light-induced transient grating technique in InN epilayers grown by pulsed MOCVD on c-plane sapphire. We show that direct Auger governs lifetime above ~1018 cm-3. measured coefficient (8...
The higher diffusivity in wider QWs increases the nonradiative recombination rate and reduces IQE.
We present a comprehensive study of photoexcited carrier dynamics in differently grown InGaN/InGaN multiple quantum well (MQW) structures, modified by insertion wide interlayer structure and subsequent growth shaped wells (rectangular, triangular, trapezoidal). This approach strain management allowed the reduction dislocation density due to gradually increasing In content shaping smooth well/barrier interfaces. A set c-oriented MQW structures emitting at 470 nm were Vilnius University,...
Enhancement of internal quantum efficiency (IQE) in InGaN wells by insertion a superlattice interlayer and applying the pulsed growth regime is investigated set time-resolved optical techniques. A threefold IQE increase was achieved structure with superlattice. It ascribed to net effect decreased electrical field due lower strain altered carrier localization conditions. Pulsed MOCVD also resulted twice higher IQE, presumably better control defects structure. An LED (light emitting diode) top...