Article
Chemistry, Analytical
Luis Francisco Garcia Russi, Ilia D. Mikhailov, Ruthber Antonio Escorcia Caballero, Jose Sierra Ortega, Gene Elizabeth Escorcia Salas
Summary: This study calculates the energy levels of shallow donors in a rolled-up quantum well under an electric field using numerical solutions of the Schrodinger equation in natural curvilinear coordinates. It is found that the density of states curves are highly sensitive to variations in donor position, spiral geometry, and applied electric field strength. Additionally, the anisotropic Stark effect of the first order leads to spike-like variations in the polarizability and dipole moment in response to the external electric field.
Article
Multidisciplinary Sciences
Jingda Wu, Dongyang Yang, Jing Liang, Max Werner, Evgeny Ostroumov, Yunhuan Xiao, Kenji Watanabe, Takashi Taniguchi, Jerry I. Dadap, David Jones, Ziliang Ye
Summary: By utilizing nondegenerate pump-probe photocurrent spectroscopy technique, the photovoltaic effect of graphene-3R-MoS2 devices was investigated, revealing an external quantum efficiency of 10% and a picosecond-fast photocurrent response speed for devices with only two atomic layers of MoS2 at low temperatures. The study uncovered the multi-component nature of the photocurrent dynamics.
Article
Engineering, Electrical & Electronic
Chongyun Jiang, Abdullah Rasmita, Hui Ma, Qinghai Tan, Zhaowei Zhang, Zumeng Huang, Shen Lai, Naizhou Wang, Sheng Liu, Xue Liu, Ting Yu, Qihua Xiong, Wei-bo Gao
Summary: A room temperature valley Hall effect can be observed in a molybdenum disulfide/tungsten diselenide van der Waals heterostructure, with electrically tunable magnitude and polarity, allowing for the creation of a bipolar valleytronic transistor.
NATURE ELECTRONICS
(2022)
Article
Nanoscience & Nanotechnology
Nikesh Patel, H. Aruni Fonseka, Yunyan Zhang, Stephen Church, Ruqaiya Al-Abri, Ana Sanchez, Huiyun Liu, Patrick Parkinson
Summary: Bottom-up grown nanostructures often exhibit significant dimensional inhomogeneity, leading to variations in electronic properties. By applying a high-throughput characterization methodology to over 15,000 nanoskived sections of strained GaAsP/GaAs radial core/shell quantum well heterostructures, it is found that these heterostructures exhibit high emission uniformity. A highly strained core/shell nanowire design is shown to minimize the dependence of emission on the quantum well width variation.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
V. Ya. Aleshkin, A. O. Rudakov
Summary: The study focuses on the theoretical analysis of the recombination process of nonequilibrium charge carriers emitting plasmons in structures with different numbers of quantum wells, especially under conditions of inverse band population. It was found that an increase in the number of quantum wells leads to a slight increase in the average recombination probability.
Article
Physics, Applied
V. Ya. Aleshkin, V. V. Rumyantsev, K. E. Kudryavtsev, A. A. Dubinov, V. V. Utochkin, M. A. Fadeev, G. Alymov, N. N. Mikhailov, S. A. Dvoretsky, F. Teppe, V. I. Gavrilenko, S. V. Morozov
Summary: The study provides a detailed theoretical analysis of nonradiative Auger recombination in narrow-gap HgCdTe quantum wells, proposing a microscopic model to calculate recombination rates and validating it against measurements. It evaluates different designs of HgCdTe/CdHgTe QWs for far-IR emitters, finding that moderate cadmium content in the QWs may favor lasing contrary to intuitive expectations. The efficiency of screening by free charge carriers contributes decisively to the suppression of Auger processes at low temperatures and high carrier concentrations.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Alexey M. Nadtochiy, Nikita Yu Gordeev, Anton A. Kharchenko, Sergey A. Mintairov, Nikolay A. Kalyuzhnyy, Yury S. Berdnikov, Yuriy M. Shernyakov, Mikhail Maximov, Alexey E. Zhukov
Summary: The modal absorptions in laser-like heterostructures containing InAs self-assembled quantum dots (QDs) and InGaAs quantum well-dots (QWDs) have been studied, with per-layer modal absorptions determined. The introduction of the layer gain constant allows for comparison of quantum heterostructures with different dimensionality, showing that the QWD layer gain constant significantly exceeds quantum well and quantum dot ones.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Optics
Mikhail K. Sotnichuk, Aleksei S. Kazakov, Ilya D. Nikolaev, Konstantin A. Drozdov, Roman V. Menshchikov, Sergey A. Dvoretsky, Nikolay N. Mikhailov, Dmitry R. Khokhlov, Anton V. Ikonnikov
Summary: Persistent photoconductivity spectra of HgTe/CdHgTe heterostructures with double quantum wells and different cap layers were studied in the range of 0.62-3.1 eV radiation excitation. It was found that the cap layer material determines the key features, local extrema, and origin of the PPC spectra. Additionally, an unusual oscillatory behavior of the PPC spectra was demonstrated to be independent of both the cap and barrier layers.
Article
Chemistry, Physical
Savas Delikanli, Onur Erdem, Furkan Isik, Hamed Dehghanpour Baruj, Farzan Shabani, Huseyin Bilge Yagci, Emek Goksu Durmusoglu, Hilmi Volkan Demir
Summary: Researchers demonstrated highly efficient amplified spontaneous emission (ASE) in solution using engineered CQWs heterostructures with low thresholds in red and green regions. The net modal gain of these CQWs is significantly higher than that of CQDs in solution, with gain cross sections two orders of magnitude larger than those of CQDs.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Yuqiang Wu, Jingang Wang, Mengtao Sun, Mingyan Chen, Lei Zhang
Summary: This study calculated the current-voltage characteristic curves, conductivity, real space charge distribution, transmission spectrum, photocurrent, and thermal current of the borophene-black phosphorus heterostructure. The results indicate that the zigzag device shows excellent photocurrent characteristics, with the direction of photocurrent adjustable by changing the wavelength of incident light and adding gate voltage. The armchair device exhibits excellent IV curve characteristics and good linear characteristics at low voltage, and also demonstrates good thermoelectric current properties. The distribution of covalent bonds formed between atoms in this heterostructure is revealed by the real space charge distribution. Our results are significant for the application of borophene-black phosphorus heterostructure in electric transport devices.
RESULTS IN PHYSICS
(2023)
Article
Physics, Applied
Adrien Khalili, Claire Abadie, Tung Huu Dang, Audrey Chu, Eva Izquierdo, Corentin Dabard, Charlie Greboval, Mariarosa Cavallo, Huichen Zhang, Stefano Pierini, Yoann Prado, Xiang Zhen Xu, Sandrine Ithurria, Gregory Vincent, Christophe Coinon, Ludovic Desplanque, Emmanuel Lhuillier
Summary: This study proposes a method to broaden the spectral range of InGaAs by using HgTe nanocrystals and alleviating lattice matching constraints in short wave infrared sensing. A diode structure is designed, where a p-type HgTe NC array and n-type InGaAs wires are used to extract minority carriers. This work opens up new possibilities for infrared detection using epitaxially grown and colloidally grown semiconductors.
APPLIED PHYSICS LETTERS
(2022)
Article
Multidisciplinary Sciences
Mahdi Hajlaoui, Stefano Ponzoni, Michael Deppe, Tobias Henksmeier, Donat Josef As, Dirk Reuter, Thomas Zentgraf, Gunther Springholz, Claus Michael Schneider, Stefan Cramm, Mirko Cinchetti
Summary: This study explores the buried quantum well states in cubic-GaN/AlN and GaAs/AlGaAs heterostructures using extremely low-energy ARPES. The results show that due to high surface roughness, energy dispersion of quantum well states in cubic-GaN/AlN cannot be observed, while quantum well states in GaAs/AlGaAs are buried too deep to be detected by this technique. The flat surface of GaAs/AlGaAs samples allows for distinct features in momentum space, revealing band structure information of the topmost surface layer of the quantum well structure.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Multidisciplinary
Ruixiang Fei, Wenshen Song, Lauren Pusey-Nazzaro, Li Yang
Summary: This study proposes a spin circular photogalvanic effect (spin CPGE) that can generate highly spin-polarized current at room temperature in parity-time (PT)-symmetric antiferromagnetic (AFM) insulators. First-principles simulations on bilayer CrI3 and room-temperature-AFM hematite confirm the effect, which shows significant spin photocurrent that is not sensitive to spin-orbit interactions. The findings give hope for realizing fast-dynamic and temperature-robust pure spin current in a variety of PT-symmetric AFM materials.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Wenkai Zheng, Li Xiang, Felipe A. . de Quesada, Mathias Augustin, Zhengguang Lu, Matthew Wilson, Aditya Sood, Fengcheng Wu, Dmitry Shcherbakov, Shahriar Memaran, Ryan E. Baumbach, Gregory T. McCandless, Julia Y. Chan, Song Liu, James H. Edgar, Chun Ning Lau, Chun Hung Lui, Elton J. G. Santos, Aaron Lindenberg, Dmitry Smirnov, Luis Balicas
Summary: Interlayer excitons are studied in hetero-bilayers of metal monochalcogenides, showing adjustable emission spectra and longer lifetimes compared to intralayer excitons. The bound electron-hole pair has a separation close to the calculated interfacial Se separation. These heterostacks have flat interfacial valence bands and are potential candidates for observing magnetism or other correlated electronic phases.
Article
Chemistry, Multidisciplinary
Fanlu Zhang, Xutao Zhang, Ziyuan Li, Ruixuan Yi, Zhe Li, Naiyin Wang, Xiaoxue Xu, Zahra Azimi, Li Li, Mykhaylo Lysevych, Xuetao Gan, Yuerui Lu, Hark Hoe Tan, Chennupati Jagadish, Lan Fu
Summary: A new growth strategy has been developed for the high-quality InGaAs/InP MQW nanowires, demonstrating excellent optical properties and potential for optoelectronic applications.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Nikita Gagrani, Kaushal Vora, Chennupati Jagadish, Hark Hoe Tan
Summary: This study investigates the characteristics and applications of p-type transparent conducting oxides (TCOs) through the deposition of SnxNiyOz films. The study explores the optical and electrical properties, band alignment, and stability of the films, as well as the behavior of LEDs using these materials. The results demonstrate the potential of SnxNiyOz as a high-performance p-type TCO for transparent electronics and optoelectronics applications.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Joshua Zheyan Soo, Bikesh Gupta, Asim Riaz, Chennupati Jagadish, Hark Hoe Tan, Siva Karuturi
Summary: To achieve low-cost and sustainable hydrogen production, developing facile approaches to fabricate water splitting (photo)electrodes based on earth-abundant catalysts is crucial. In this study, a substrate-agnostic method of depositing NiFe layered double hydroxide (LDH) catalyst on diverse substrates for water splitting (photo)anodes is demonstrated. The deposited catalyst electrodes exhibit consistent and sustained water splitting performance across various substrates, and possess regenerative capabilities.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Sonachand Adhikari, Mykhaylo Lysevych, Chennupati Jagadish, Hark Hoe Tan
Summary: Selective area growth of Ga-polar GaN nanowires by metal organic chemical vapor deposition allows for the control of nanowire dimensions by adjusting the partial pressures of the constituent gases.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Chemistry, Multidisciplinary
Teja Potocnik, Peter J. Christopher, Ralf Mouthaan, Tom Albrow-Owen, Oliver J. Burton, Chennupati Jagadish, Hark Hoe Tan, Timothy D. Wilkinson, Stephan Hofmann, Hannah J. Joyce, Jack A. Alexander-Webber
Summary: We present a high-throughput method for identifying and characterizing individual nanowires, and for designing electrode patterns with high alignment accuracy. Our method utilizes an optimized marker system called LithoTag, which allows for nanometer-scale position determination of nanostructures. By incorporating computer vision algorithms, we can obtain location and property data for individual nanowires. Experimental results demonstrate the effectiveness of this method in automating nanodevice processing and improving fabrication efficiency.
Article
Physics, Applied
Kousik Bera, Dipankar Chugh, Hark Hoe Tan, Anushree Roy, Chennupati Jagadish
Summary: Wafer-scale thin films of hexagonal boron nitride have exceptional thermal and mechanical properties. The characteristics of substrates influence the physical and mechanical properties of these films. The roughness and height modulation at the surface of the substrates play a crucial role in determining substrate-mediated mechanical strain inhomogeneity in these films. Furthermore, there is a significant difference in the thermal evolution of strain in these films depending on substrate materials, with slippage playing a more significant role in 2 nm films than in 30 nm films.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Mohammad Rashidi, Tuomas Haggren, Chennupati Jagadish, Hark Hoe Tan
Summary: This research presents a hybrid nanolaser that supports both Fabry-Perot and random lasing modes. The study demonstrates different lasing properties of these modes, including wavelength, polarization, and coherency. Practical methods are introduced to distinguish these modes, and thermal tuning is used to switch between different laser types.
Article
Nanoscience & Nanotechnology
Tuomas Haggren, Julie Tournet, Chennupati Jagadish, Hark Hoe Tan, Jani Oksanen
Summary: A scalable multilayer epitaxial lift-off process is demonstrated, which allows efficient removal of epitaxially grown materials from their host substrate without external strains. The films retain good integrity after lift-off and can be further processed into devices. Cost analysis shows a 4-to-6-fold reduction in cost compared to the single-layer epitaxial lift-off process, making it significant for III-V photovoltaics and other technologies relying on thin-film III-V semiconductors.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Optics
Wei Wen Wong, Naiyin Wang, Chennupati Jagadish, Hark Hoe Tan
Summary: This study presents a novel approach to realize on-chip microlasers with directional emission in an all-dielectric, bottom-up grown material system. By coupling the laser emission into a vertical nanowire, efficient optical coupling is achieved and the emission directivity and side mode suppression can be improved by tuning the geometric parameters of the system.
LASER & PHOTONICS REVIEWS
(2023)
Article
Physics, Applied
Lifeng Xiang, Yang Shi, Wei Chao, Huanyu Zhang, Qiang Li, Wenjie Hu, Wenbin Wang, Hangwen Guo, Changlin Zheng, Joanne Etheridge, Lifeng Yin, Yinyan Zhu, Xiaodong Zhou, Jian Shen
Summary: For perovskite manganites, achieving low-field colossal magnetoresistance (CMR) is crucial. In this study, the magnetic field driven insulator-to-metal transition in La1-x-yPrxCayMnO3 is investigated using real space magnetic force microscopy (MFM). Three stages of the phase transition are observed, with distinct features in domain nucleation and growth. MFM reveals that domain growth requires a lower field than domain nucleation, providing critical information for achieving low-field CMR.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Jun-Wei Liao, Zhen-Ting Huang, Chia-Hung Wu, Nikita Gagrani, Hark Hoe Tan, Chennupati Jagadish, Kuo-Ping Chen, Tien-Chang Lu
Summary: In this study, localized surface plasmon lasing at room temperature in the communication band was achieved using metallic nanoholes as plasmonic nanocavity and InP nanowires as gain medium. Optimization of laser performance was demonstrated through coupling between two metallic nanoholes, allowing for manipulation of lasing properties. These plasmonic nanolasers offer lower power consumption, smaller mode volumes, and higher spontaneous emission coupling factors, making them promising for high-density sensing and photonic integrated circuits.
Article
Nanoscience & Nanotechnology
Bikesh Gupta, Doudou Zhang, Hongjun Chen, Chennupati Jagadish, Hark Hoe Tan, Siva Karuturi
Summary: This study presents a novel approach for fabricating high-performance solar cells based on InP heterojunctions using a solution-processed ferri-hydrite (Fh) electron-selective contact (ESC). The champion cell efficiency of 16.6% is achieved, which is a significant improvement over those from previous studies using other solution-processed ESC materials. The Fh layer not only selectively extracts photogenerated electrons from InP but also simultaneously serves as a surface protection layer, improving the cell's long-term stability.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Wei Wen Wong, Naiyin Wang, Bryan D. D. Esser, Stephen A. A. Church, Li Li, Mark Lockrey, Igor Aharonovich, Patrick Parkinson, Joanne Etheridge, Chennupati Jagadish, Hark Hoe Tan
Summary: In this study, we utilize the selective area epitaxy method to deterministically engineer thousands of microring lasers on a single chip. By elucidating a detailed growth mechanism and controlling the adatom diffusion lengths, we achieve ultrasmooth cavity sidewalls. These engineered devices exhibit a tunable emission wavelength in the telecommunication O-band and show low-threshold lasing with high device efficacy across the chip. This work marks a significant milestone toward the implementation of a fully integrated III-V materials platform for next-generation high-density integrated photonic and optoelectronic circuits.
Article
Chemistry, Multidisciplinary
Brenton Cook, Philipp Reineck, Thomas Shiell, Jodie Bradby, Bryan D. Esser, Joanne Etheridge, Bianca Haberl, Reinhard Boehler, David R. Mckenzie, Dougal G. McCulloch
Summary: Diamond is a crucial material for biosensors, quantum computing, and space components due to its unique properties at the nanoscale. Researchers have successfully synthesized oriented, faceted diamond particles by flash laser heating of glassy carbon, and observed their microstructure and periodicity.
Article
Materials Science, Multidisciplinary
Weilun Li, Wenming Tong, Joanne Etheridge, Alison M. Funston
Summary: Shape and size control of metal nanocrystals is important for tuning their physicochemical properties. In this study, the growth mechanisms of gold nanocuboids and the influence of copper additives were investigated. The presence of copper additives led to asymmetrical growth and the formation of nanobars instead of nanocubes, accompanied by a reduction in particle size. This was attributed to a combination of rapid deposition on {111} facets and slow surface diffusion rate introduced by surface copper.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
