Understanding the impact of the alloy micro-structure on carrier transport becomes important when designing III-nitride-based light emitting diode (LED) structures. In this work, we study the impact of alloy fluctuations on the hole carrier transport in (In,Ga)N single and multi-quantum well systems. To disentangle hole transport from electron transport and carrier recombination processes, we focus our attention on uni-polar (--) systems. The calculations employ our recently established multi-scale simulation framework that connects atomistic tight-binding theory with a macroscale drift-diffusion model. In addition to alloy fluctuations, we pay special attention to the impact of quantum corrections on hole transport. Our calculations indicate that results from a virtual crystal approximation present an upper limit for the hole transport in a -- structure in terms of the current-voltage characteristics. Thus we find that alloy fluctuations can have a detrimental effect on hole transport in (In,Ga)N quantum well systems, in contrast to uni-polar electron transport. However, our studies also reveal that the magnitude by which the random alloy results deviate from virtual crystal approximation data depends on several factors, e.g. how quantum corrections are treated in the transport calculations.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9170672 | PMC |
http://dx.doi.org/10.1007/s11082-022-03752-2 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Chandra Family Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78712, United States.
A device architecture based on heterostructure WSe/organic semiconductor field-effect transistors (FETs) is demonstrated in which ambipolar conduction is virtually eliminated, resulting in essentially unipolar FETs realized from an ambipolar semiconductor. For p-channel FETs, an electron-accepting organic semiconductor such as hexadecafluorocopperphthalocyanine (FCuPc) is used to form a heterolayer on top of WSe to effectively trap any undesirable electron currents. For n-channel FETs, a hole-accepting organic semiconductor such as pentacene is used to reduce the hole currents without affecting the electron currents.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Physics, Riphah International University, Campus Lahore, Lahore 54000, Pakistan.
To advance off-grid energy solutions, developing flexible photobatteries capable of direct light charging is essential. This study presents an innovative photobattery architecture that incorporates zinc oxide (ZnO) as an electron-transporting and hole-blocking layer, combined with a hybrid methylammonium tin iodide composite with poly-triarylamine (MASnI/PTAA) for light absorption and hole transport. PTAA facilitates efficient hole transport to the anode, thereby enhancing charge separation and reducing recombination losses.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Institute of New Energy Technology, College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China.
Trigonal selenium (t-Se) is a promising wide-band-gap photovoltaic material with a high absorption coefficient, abundant resources, simple composition, nontoxicity, and a low melting point, making it suitable for absorbers in advanced indoor and tandem photovoltaic applications. However, severe electrical losses at the rear interface of the t-Se absorber, caused by work function and lattice mismatches, limit the voltage output and overall performance. In this study, a strategy to enhance carrier transport and collection by modifying interfacial chemical interactions is proposed.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
Institute of Polymer Optoelectronic Materials and Devices, Guangdong Basic Research Center of Excellence for Energy and Information Polymer Materials, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China.
Simultaneous improvement in power conversion efficiency (PCE) and device stability is very important for organic solar cells (OSCs). Herein, oligothiophene-based polymer W19 with excellent solvent resistance is exploited as a polymer thin layer to optimize the active layer morphology and then device efficiency and stability. Polymer W19 possesses a simple skeleton of trifluromethyl-substituted dithienoquinoxaline and quaterthiophene, whose thin layer shows suitable energy level, low surface energy, and strong interchain aggregation, leading to outstanding solvent resistance and excellent hole transport ability.
View Article and Find Full Text PDFSmall
January 2025
Central Research Institute, BOE Technology Group Co. Ltd, Beijing, 100176, China.
For quantum-dot light-emitting diodes (QLED), electrical aging commonly introduces collective aging sources across all layers, making it difficult to isolate the impact of each layer on electroluminescence (EL) degradation. In this work, a layer-selective aging method using active photoexcitation is proposed, in which the photoexcitation wavelength is used to selectively target specific layers for exciton generation, and an electrical bias is applied to induce photocurrent and create charges. An iterative aging-sampling (A-S) procedure is used to link aging conditions to EL degradation.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!