Article
Engineering, Chemical
Pengcheng Su, Miaomiao Jia, Junping Huang, Wanbin Li, Chuyang Y. Tang
Summary: In this study, uniform and multilayered polyamide-graphene oxide TFN membranes were assembled by a simple and controllable strategy called multilayer deposition. These membranes showed significantly increased NaCl and antibiotic rejection, as well as enhanced antifouling property in reverse osmosis/nanofiltration processes.
Article
Chemistry, Analytical
Yongjuan Zhao, Wenge Wu, Yunping Cheng, Wentao Yan
Summary: This paper investigates the influence of process parameters on the surface quality of an aluminum oxide thin film used as a transition layer in a thin-film strain micro-sensor. By optimizing the process parameters, the adhesion between the insulating-layer silicon nitride film and the aluminum substrate can be improved.
Article
Chemistry, Multidisciplinary
Wangying Xu, Chuyu Xu, Zhibo Zhang, Weicheng Huang, Qiubao Lin, Shuangmu Zhuo, Fang Xu, Xinke Liu, Deliang Zhu, Chun Zhao
Summary: Water-induced nanometer-thin crystalline indium praseodymium oxide thin-film transistors (TFTs) with improved performance and durability by Pr doping were successfully reported. The optimized In-Pr-O TFT demonstrated state-of-the-art electrical performance.
Article
Materials Science, Multidisciplinary
Claudia Campos, Natalia Herguedas, Enrique Carretero
Summary: This research determined the optimal conditions for depositing thin silver layers in low-emissivity coatings. The study found that lower power and higher argon flow led to higher transmittance and lower emissivity. The research also emphasized the importance of silver thickness in coating properties.
Article
Chemistry, Multidisciplinary
Yongbo Wu, Linfeng Lan, Penghui He, Yilong Lin, Caihao Deng, Siting Chen, Junbiao Peng
Summary: The study systematically investigated solution-processed AlOx dielectrics, revealing that the capacitance of AlOx is critically dependent on frequency when annealed at low temperatures and subjected to water treatment. These findings highlight the impact of mobile ions on the frequency-dependent capacitance of solution-processed AlOx dielectrics.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Multidisciplinary
M. Isabelle Buschges, Rudolf C. Hoffmann, Anna Regoutz, Christoph Schlueter, Jorg J. Schneider
Summary: The multilayered heterostructures of In2O3, SnO2, and Al2O3 showed improved properties in thin-film transistors (TFT), with high transparency and enhanced semiconducting behavior achieved through atomic layer deposition. Incorporation of only two monolayers of Al2O3 effectively suppressed oxygen vacancies, leading to improved TFT characteristics.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Optics
Benyamin Darzi, Amin Ghadi, Arezou Rashidi
Summary: By using the Transfer Matrix method and Abele's Matrix method, absorptive multilayer structures for thin-film solar cells have been proposed, which can efficiently absorb the solar spectrum and maintain high absorption rates at different angles. The absorption rate has been significantly increased by considering the dispersion effect, and the structures have been protected against solar intensity fluctuations through the reduction of magnetic fields and the adjustment of sunlight intensity.
Article
Nanoscience & Nanotechnology
Chunqi Jin, Yuanmu Yang
Summary: Researchers have proposed an optical filter for isotropic image differentiation, fabricated using mature thin film deposition technique, which can be used for various input polarizations in transmission mode. This thin film filter can conveniently enhance and process images in real time.
Article
Materials Science, Coatings & Films
Chao Wu, Fan Lin, Yanzhang Fu, Yingjun Zeng, Guochun Chen, Lida Xu, Xiaochuan Pan, Qinnan Chen, Daoheng Sun, Zhenyin Hai
Summary: In this study, thin-film strain gauges (TFSGs) were fabricated on superalloy substrate by co-sintering process for the first time. Compared with layer-by-layer sintering, the weak interface constraint between the top and sub layers of co-sintered TFSG allows the free in-plane shrinkage of the Pt resistance grid. Owing to the remarkable advantages of the co-sintering process, the co-sintered Pt TFSG not only inherits the high-temperature insulation of the layer-by-layer sintered insulating layer, but also significantly increases the high-temperature stability of the Pt grid resistance.
SURFACE & COATINGS TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Chung-Lun Yu, Subramanian Sakthinathan, Min-Te Lu, Shu-Tzu Yu, Cheng-Yung Kuo, Yu-Feng You, Te-Wei Chiu
Summary: In this study, Delafossite CuAlO2/AlN thin films were prepared using a spin coating method. The aim was to explore the preparation of CuO on AlN film and form CuAlO2 through high-temperature annealing, as well as investigate the properties resulting from different temperature treatments. The results showed that CuAlO2/AlN film can be easily and affordably prepared using spin coating, and AlN has excellent characteristics that make it suitable for various applications.
Article
Materials Science, Multidisciplinary
Richard Drevet, Pavel Soucek, Pavel Mares, Martin Dubau, Zsolt Czigany, Katalin Balazsi, Petr Vasina
Summary: This research focuses on the synthesis of multilayer thin films of aluminum oxide and tantalum oxide for dielectric applications. The films are made of two, four, or eight oxide layers produced by physical vapor deposition (PVD). The morphology and crystallinity of the films are influenced by the interface between the oxide layers and can be changed by thermal annealing. The dielectric strength of the films is also studied and compared to single layers of Al2O3 and Ta2O5.
Article
Chemistry, Multidisciplinary
Tangyou Sun, Furong Shui, Xiancui Yang, Zhiping Zhou, Rongqiao Wan, Yun Liu, Cheng Qian, Zhimou Xu, Haiou Li, Wenjing Guo
Summary: This study developed a simple lithography-free process to obtain large-scale surface nano-pillar arrays with excellent anti-reflection performance. The CSNP nanostructured Si showed polarization insensitivity and low dependence on incident angles over the whole spectrum. Thin film solar cell models based on the CSNP structure showed significant improvement in efficiency compared to other structured ones.
Article
Multidisciplinary Sciences
Hugo Hartl, Joseph Davies, Geoffrey Will, Kostya Ostrikov, Jennifer MacLeod
Summary: This study presents a new method for directly fabricating a superhydrophobic surface coating on mild steel. Dielectric barrier discharge (DBD) plasma was used to convert a liquid small-molecule precursor to a solid film through plasma-assisted on-surface polymerization. The properties of the coating were analyzed using various techniques, including microscopy, spectroscopy, and contact angle measurement. The results showed that the wettability of the films could be controlled by adjusting the plasma parameters and incorporating graphene nanoplatelets in the precursor. High-dose plasma exposures of the nanoplatelet-containing precursor resulted in the formation of superhydrophobic films with water contact angles above 150 degrees. However, the superhydrophobic coating provided limited corrosion protection according to potentiodynamic polarisation tests.
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Physical
Pandey Rajagopalan, Shuyi Huang, Lin Shi, Haoze Kuang, Hao Jin, Shurong Dong, Wenhua Shi, Xiaozhi Wang, Jikui Luo
Summary: Recent developments in contact electrification and triboelectricity have led to a new understanding of the dynamic nature of materials under strain, complicating the traditional static triboelectric series scale. This research proposes a self-powered nanoscale thickness monitoring system using advanced techniques to study the intricate mechanisms of charge transfer during contact electrifications.
Article
Biochemistry & Molecular Biology
Yaru Pan, Xihui Liang, Zhihao Liang, Rihui Yao, Honglong Ning, Jinyao Zhong, Nanhong Chen, Tian Qiu, Xiaoqin Wei, Junbiao Peng
Summary: Multi-component metal oxide films can achieve good performances in several aspects, such as leakage current density and capacitance density. The AMYZO(x) group has the lowest leakage current density, while the HMYZO(x) group has the highest capacitance density.
Article
Nanoscience & Nanotechnology
Capucine Tong, Thomas Bidaud, Eero Koivusalo, Marcelo Rizzo Piton, Mircea Guina, Helder Vinicius Avanco Galeti, Yara Galvao Gobato, Andrea Cattoni, Teemu Hakkarainen, Stephane Collin
Summary: Cathodoluminescence mapping is utilized to investigate the electron concentration gradient of Te-doped GaAs nanowires, revealing distinct electron concentration levels and gradients in nanowires grown at different temperatures.
Article
Optics
Yicheng Wang, Pavel Loiko, Yongguang Zhao, Zhongben Pan, Weidong Chen, Mark Mero, Xiaodong Xu, Jun Xu, Xavier Mateos, Arkady Major, Mircea Guina, Valentin Petrov, Uwe Griebner
Summary: In this study, a Tm,Ho:CALGO laser passively mode-locked by a GaSb-based SESAM is reported. The laser generates pulses as short as 52 fs, with a central wavelength of 2015 nm and a broad spectral bandwidth of 82 nm. The laser performance is attributed to the combined gain profiles of the dopants and the polarized spectroscopic properties of Ho3+ ions.
Article
Optics
S. C. Burd, J. -P. Penttinen, P. -Y. Hou, H. M. Knaack, S. Ranta, M. Maki, E. Kantola, M. Guina, D. H. Slichter, D. Leibfried, A. C. Wilson
Summary: This article presents two systems based on vertical-external-cavity surface-emitting lasers (VECSELs) that can generate ultraviolet laser light at 235 and 313 nm wavelengths, suitable for quantum information processing with trapped beryllium ions. Each system includes a compact, single-frequency, continuous-wave VECSEL that produces high-power near-infrared light and can be tuned over tens of nanometers. One system produces 2.4 W of power at 940 nm, which is converted to 54 mW of 235 nm light for photoionization of neutral beryllium atoms. The other system uses a gain mirror based on GaInNAs/GaAs quantum wells, extending the wavelength above 1200 nm with manageable strain in the GaAs lattice, and generates 1.6 W at 1252 nm, which is converted to 41 mW of 313 nm light for laser cooling of trapped 9Be+ ions and quantum state preparation and detection. The 313 nm system is also suitable for implementing high-fidelity quantum gates.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Omer Donmez, Mustafa Aydin, Selman Mutlu, Janne Puustinen, Joonas Hilska, Mircea Guina, Ayse Erol
Summary: We present experimental and analytical results on hot electron transport in as-grown and annealed n-type modulation-doped Al0.15Ga0.85As/GaAs0.96Bi0.4 quantum well structures. The drift mobility and velocity of the annealed sample are lower due to the increased 2D electron density caused by annealing. Hot electron transport occurs in parallel mode, and inter-valley transfer dominates at higher electric fields.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2023)
Article
Optics
Nouman Zia, Samu-pekka Ojanen, Jukka Viheriala, Eero Koivusalo, Joonas Hilska, Heidi Tuorila, Mircea Guina
Summary: This paper presents a hybrid laser that combines GaSb-based semiconductor gain chips with Si3N4 photonic integrated circuits. The low-loss features of Si3N4 waveguides are utilized to integrate a tunable Si3N4 Vernier mirror. The laser exhibits a maximum output power of 15 mW and a tuning range of about 90 nm at room temperature. The low-loss performance of various Si3N4 building blocks for photonic integrated circuits is also confirmed.
Article
Energy & Fuels
Andrea Scaccabarozzi, Stefano Vichi, Sergio Bietti, Federico Cesura, Timo Aho, Mircea Guina, Federica Cappelluti, Maurizio Acciarri, Stefano Sanguinetti
Summary: We investigate the impact of quantum dot aspect ratio on the sub-gap absorption properties of GaAs/AlGaAs quantum dot intermediate band solar cells. Using droplet epitaxy, we grow AlGaAs solar cells with GaAs quantum dots, which allows for strain-free nanostructures with lattice matched materials. By varying the dot aspect ratio, we can tune the energy levels of the intermediate band, thereby altering the sub-gap absorption spectrum and charge carrier extraction. The tradeoff between thermal and optical extraction is crucial for the proper functioning of the intermediate band solar cells, with the photonic extraction mechanism from the quantum dots becoming dominant at room temperature.
PROGRESS IN PHOTOVOLTAICS
(2023)
Article
Engineering, Electrical & Electronic
Philipp Tatar-Mathes, Hoy-My Phung, Aaron Rogers, Patrik Rajala, Sanna Rant, Mircea Guina, Hermann Kahle
Summary: This study presents the operation of a semiconductor membrane external-cavity surface-emitting laser (MECSEL) using a gain membrane with a non-resonant cavity design. The MECSEL delivers watt-level output power, comparable to state-of-the-art results. The research shows that the design criteria for the MECSEL gain region can be relaxed compared to designs using distributed Bragg reflectors, minimizing the impact of defective Fabry-Perot micro-cavity effects.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2023)
Article
Optics
Samu-Pekka Ojanen, Jukka Viheriala, Nouman Zia, Eero Koivusalo, Joonas Hilska, Heidi Tuorila, Mircea Guina
Summary: Photonic integrated circuits fabricated using a Si3N4 waveguide platform exhibit low losses in a wide wavelength region. A high-performance integrated laser with broad wavelength tunability near a 2.6 μm wavelength region is demonstrated, based on a Si3N4 photonic integrated circuit incorporating a tunable reflector and a AlGaInAsSb/GaSb quantum-well gain element. The platform also supports low propagation loss up to 3.5 μm.
LASER & PHOTONICS REVIEWS
(2023)
Article
Optics
D. Mitten, M. Hart, S. H. Warner, J. -P. Penttinen, M. Guina, Y. Kaneda
Summary: A vertical external cavity surface emitting laser (VECSEL) has been developed for a sodium guide star application. Stable single frequency operation with 21 W of output power near 1178 nm with multiple gain elements while lasing in the TEM00 mode has been achieved. This is the first demonstration of a high power single frequency VECSEL using a twisted-mode configuration and multiple gain mirrors located at the cavity folds.
Article
Physics, Applied
Y. Q. Huang, V Polojarvi, A. Aho, R. Isoaho, T. Hakkarainen, M. Guina, I. A. Buyanova, W. M. Chen
Summary: This study demonstrates the existence of nonlinear spin response in nonmagnetic materials and showcases it in a (Ga, N)As-InAs quantum dot coupled all-semiconductor nanostructure. The observed spin nonlinearity can be conveniently tuned with an external magnetic field and potentially operates at a speed exceeding 1 GHz.
PHYSICAL REVIEW APPLIED
(2023)
Article
Optics
Samu-Pekka Ojanen, Jukka Viheriala, Nouman Zia, Eero Koivusalo, Joonas Hilska, Heidi Tuorila, Mircea Guina
Summary: A discrete, tunable photonic integrated laser is demonstrated for multiwavelength spectroscopy. The laser combines a reflective semiconductor optical amplifier with a photonic integrated circuit, allowing for switching between three distinct emission wavelengths. The design simplifies the tuning mechanism compared to other hybrid lasers.
LASER & PHOTONICS REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Tristan Smolka, Michal Rygala, Joonas Hilska, Janne Puustinen, Eero Koivusalo, Mircea Guina, Marcin Motyka
Summary: The optical properties of GaSbBi layers grown on GaSb (100) substrates with different bismuth contents were investigated. The band gaps of the materials were determined using Fourier-transform photoluminescence spectra, revealing the presence of localized states connected to bismuth clustering. Time-resolved photoluminescence measurements based on single-photon counting were used to determine the characteristic photoluminescence decay time constants, which showed an increase with increasing bismuth content and clustering effects.
Article
Energy & Fuels
Janne Puustinen, Joonas Hilska, Arto Aho, Esperanza Luna, Antti Fihlman, Mircea Guina
Summary: The development of low bandgap GaAsNBi solar cells grown using MBE is reported, and the As/Ga flux ratio is found to play an important role in controlling the solar cell performance.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2024)
Proceedings Paper
Nanoscience & Nanotechnology
Jukka Viheriala, Topi Uusitalo, Heikki Virtanen, Behzad Namvar, Patrik Rajala, Sanna Ranta, Teemu Hakkarainen, Antti Tukiainen, Guilhem Almuneau, Mircea Guina
Summary: This paper presents the development of vertical cavity surface emitting lasers (VCSELs) operating at 4.2K for energy efficient optical links between cryogenic systems and room-temperature data storage systems. The design considerations, material models, and validation of required electro-optical-thermal models are discussed. Successful operation at mA-level injection is demonstrated.
2023 IEEE PHOTONICS SOCIETY SUMMER TOPICALS MEETING SERIES, SUM
(2023)
