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Felici R, Baroni T, Carlà F, Cioffi N, Di Benedetto F, Fontanesi C, Giaccherini A, Giurlani W, Gonidec M, Lavacchi A, Berretti E, Marcantelli P, Montegrossi G, Bonechi M, Picca RA, Poggini L, Russo F, Sportelli MC, Torsi L, Innocenti M. On the Electrochemical Growth of a Crystalline p-n Junction From Aqueous Solutions. Chemistry 2024; 30:e202401403. [PMID: 38818578 DOI: 10.1002/chem.202401403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/29/2024] [Accepted: 05/29/2024] [Indexed: 06/01/2024]
Abstract
Our society largely relies on inorganic semiconductor devices which are, so far, fabricated using expensive and complex processes requiring ultra-high vacuum equipment. Here we report on the possibility of growing a p-n junction taking advantage of electrochemical processes based on the use of aqueous solutions. The growth of the junction has been carried out using the Electrochemical Atomic Layer Deposition (E-ALD) technique, which allowed to sequentially deposit two different semiconductors, CdS and Cu2S, on an Ag(111) substrate, in a single procedure. The growth process was monitored in situ by Surface X-Ray Diffraction (SXRD) and resulted in the fabrication of a thin double-layer structure with a high degree of crystallographic order and a well-defined interface. The high-performance electrical characteristics of the device were analysed ex-situ and show the characteristic feature of a diode.
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Affiliation(s)
| | - Tommaso Baroni
- Department of Earth Sciences, University of Florence, Florence, 50121, Italy
| | - Francesco Carlà
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, OX11 0DE, UK
| | - Nicola Cioffi
- Department of Chemistry, University of Bari "Aldo Moro", Bari, 70126, Italy
- Center for Colloid and Surface Science (CSGI), Sesto Fiorentino, 50019, Italy
| | | | - Claudio Fontanesi
- Department of Engineering "Enzo Ferrari", University of Modena and Reggio Emilia, Modena, 41125, Italy
- National Interuniversity Consortium of Materials Science and Technology (INSTM), Florence, 50121, Italy
| | - Andrea Giaccherini
- Department of Industrial Engineering, University of Florence, Florence, 50139, Italy
| | - Walter Giurlani
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, 50019, Italy
- National Interuniversity Consortium of Materials Science and Technology (INSTM), Florence, 50121, Italy
| | - Mathieu Gonidec
- ICMCB, Université Bordeaux and CNRS UMR 5026, Pessac, 33600, France
| | - Alessandro Lavacchi
- Institute of Chemistry of Organometallic Compounds (ICCOM) -, National Research Council (CNR), Sesto Fiorentino, 50019, Italy
| | - Enrico Berretti
- Institute of Chemistry of Organometallic Compounds (ICCOM) -, National Research Council (CNR), Sesto Fiorentino, 50019, Italy
| | - Patrick Marcantelli
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, 50019, Italy
| | - Giordano Montegrossi
- Institute of Geosciences and Georesources: Florence site (CNR-IGG), National Research Council, Florence, 50121, Italy
| | - Marco Bonechi
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, 50019, Italy
| | - Rosaria A Picca
- Department of Chemistry, University of Bari "Aldo Moro", Bari, 70126, Italy
- Center for Colloid and Surface Science (CSGI), Sesto Fiorentino, 50019, Italy
| | - Lorenzo Poggini
- Institute of Chemistry of Organometallic Compounds (ICCOM) -, National Research Council (CNR), Sesto Fiorentino, 50019, Italy
| | - Francesca Russo
- Department of Industrial Engineering, University of Trento, Via Sommarive 9, Trento, 38123, Italy
| | - Maria C Sportelli
- Department of Chemistry, University of Bari "Aldo Moro", Bari, 70126, Italy
- Center for Colloid and Surface Science (CSGI), Sesto Fiorentino, 50019, Italy
| | - Luisa Torsi
- Department of Chemistry, University of Bari "Aldo Moro", Bari, 70126, Italy
| | - Massimo Innocenti
- Center for Colloid and Surface Science (CSGI), Sesto Fiorentino, 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, 50019, Italy
- National Interuniversity Consortium of Materials Science and Technology (INSTM), Florence, 50121, Italy
- Institute of Chemistry of Organometallic Compounds (ICCOM) -, National Research Council (CNR), Sesto Fiorentino, 50019, Italy
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2
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Briones E, Gutierrez A, Tapia-Contreras M, Cortes-Mestizo I, Briones J. Antireflective properties of Al 2O 3/SiO 2 multilayer stacks for GaAs solar cells. APPLIED OPTICS 2023; 62:6007-6015. [PMID: 37706955 DOI: 10.1364/ao.487452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 07/03/2023] [Indexed: 09/15/2023]
Abstract
Multilayer (ML) thin films are an optical engineering strategy to address reflectivity losses in GaAs photovoltaic devices, enhancing the power conversion of light around a single wavelength. Inspired by the enhanced response of periodic ML Bragg mirrors, the authors introduce quite simple antireflective designs based on two periods and single periods of A l 2 O 3/S i O 2 bilayer stacks. The reflectivity losses of the systems are evaluated with the aid of numerical simulations, and their dimensions are optimized to enhance the transmission of plane waves towards GaAs substrates. Reflectivity losses are evaluated at angles off the normal for s- and p-polarized light, exhibiting gains at broader angles and the quenching of undesired s-t o-p optical anisotropy, inherent to GaAs substrates. ML stacks were fabricated by RF sputtering deposition on G a A s-n and p+ type substrates and characterized by UV-Vis spectroscopy techniques to evaluate the role of carriers on coating performance.
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3
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Moazzami Gudarzi M, Aboutalebi SH. Mapping the Binding Energy of Layered Crystals to Macroscopic Observables. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2204001. [PMID: 36253141 PMCID: PMC9685473 DOI: 10.1002/advs.202204001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Van der Waals (vdW) integration of two dimensional (2D) crystals into functional heterostructures emerges as a powerful tool to design new materials with fine-tuned physical properties at an unprecedented precision. The intermolecular forces governing the assembly of vdW heterostructures are investigated by first-principles models, yet translating the outcome of these models to macroscopic observables in layered crystals is missing. Establishing this connection is, therefore, crucial for ultimately designing advanced materials of choice-tailoring the composition to functional device properties. Herein, components from both vdW and non-vdW forces are integrated to build a comprehensive framework that can quantitatively describe the dynamics of these forces in action. Specifically, it is shown that the optical band gap of layered crystals possesses a peculiar ionic character that works as a quantitative indicator of non-vdW forces. Using these two components, it is then described why only a narrow range of exfoliation energies for this class of materials is observed. These findings unlock the microscopic origin of universal binding energy in layered crystals and provide a general protocol to identify and synthesize new crystals to regulate vdW coupling in the next generation of heterostructures.
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Affiliation(s)
- Mohsen Moazzami Gudarzi
- National Graphene InstituteUniversity of ManchesterManchesterM13 9PLUK
- Department of MaterialsSchool of Natural SciencesThe University of ManchesterManchesterM13 9PLUK
| | - Seyed Hamed Aboutalebi
- Condensed Matter National LaboratoryInstitute for Research in Fundamental SciencesTehran19395‐5531Iran
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4
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Li X, Chen X, Wei N, Chen C, Yang Z, Xie H, He J, Dong N, Dan Y, Wang J. Nonlinear absorption and integrated photonics applications of MoSSe. OPTICS EXPRESS 2022; 30:32924-32936. [PMID: 36242344 DOI: 10.1364/oe.465566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 08/12/2022] [Indexed: 06/16/2023]
Abstract
This study explores the wavelength-dependent and pulse-width-dependent nonlinear optical properties of liquid-phase exfoliated molybdenum sulfide selenide (MoSSe) nanosheets. The saturable absorption response of MoSSe nanosheets in the visible region is better than that in the near-infrared region, and the response under 6-ns pulse excitation is better than that of a 380-fs pulse. Furthermore, based on the first-principles calculations, we designed a phase modulator and optimized its structure by integrating a monolayer MoSSe into a silicon slot waveguide. The simulation results revealed that the phase shift could achieve a high optical extinction. Consequently, MoSSe exhibits satisfactory nonlinear optical properties and an excellent potential for applications in optoelectronic devices.
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5
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Pierucci D, Mahmoudi A, Silly M, Bisti F, Oehler F, Patriarche G, Bonell F, Marty A, Vergnaud C, Jamet M, Boukari H, Lhuillier E, Pala M, Ouerghi A. Evidence for highly p-type doping and type II band alignment in large scale monolayer WSe 2/Se-terminated GaAs heterojunction grown by molecular beam epitaxy. NANOSCALE 2022; 14:5859-5868. [PMID: 35362486 DOI: 10.1039/d2nr00458e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Two-dimensional materials (2D) arranged in hybrid van der Waals (vdW) heterostructures provide a route toward the assembly of 2D and conventional III-V semiconductors. Here, we report the structural and electronic properties of single layer WSe2 grown by molecular beam epitaxy on Se-terminated GaAs(111)B. Reflection high-energy electron diffraction images exhibit sharp streaky features indicative of a high-quality WSe2 layer produced via vdW epitaxy. This is confirmed by in-plane X-ray diffraction. The single layer of WSe2 and the absence of interdiffusion at the interface are confirmed by high resolution X-ray photoemission spectroscopy and high-resolution transmission microscopy. Angle-resolved photoemission investigation revealed a well-defined WSe2 band dispersion and a high p-doping coming from the charge transfer between the WSe2 monolayer and the Se-terminated GaAs substrate. By comparing our results with local and hybrid functionals theoretical calculation, we find that the top of the valence band of the experimental heterostructure is close to the calculations for free standing single layer WSe2. Our experiments demonstrate that the proximity of the Se-terminated GaAs substrate can significantly tune the electronic properties of WSe2. The valence band maximum (VBM, located at the K point of the Brillouin zone) presents an upshift of about 0.56 eV toward the Fermi level with respect to the VBM of the WSe2 on graphene layer, which is indicative of high p-type doping and a key feature for applications in nanoelectronics and optoelectronics.
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Affiliation(s)
- Debora Pierucci
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France.
| | - Aymen Mahmoudi
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France.
| | - Mathieu Silly
- Synchrotron-SOLEIL, Université Paris-Saclay, Saint-Aubin, BP48, F91192 Gif sur Yvette, France
| | - Federico Bisti
- Dipartimento di Scienze Fisiche e Chimiche, Università dell'Aquila, Via Vetoio 10, 67100 L'Aquila, Italy
| | - Fabrice Oehler
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France.
| | - Gilles Patriarche
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France.
| | - Frédéric Bonell
- Université Grenoble Alpes, CNRS, CEA, Grenoble INP, IRIG-Spintec, 38054, Grenoble, France
| | - Alain Marty
- Université Grenoble Alpes, CNRS, CEA, Grenoble INP, IRIG-Spintec, 38054, Grenoble, France
| | - Céline Vergnaud
- Université Grenoble Alpes, CNRS, CEA, Grenoble INP, IRIG-Spintec, 38054, Grenoble, France
| | - Matthieu Jamet
- Université Grenoble Alpes, CNRS, CEA, Grenoble INP, IRIG-Spintec, 38054, Grenoble, France
| | - Hervé Boukari
- Université Grenoble Alpes, CNRS and Grenoble INP, Institut Néel, F-38000 Grenoble, France
| | - Emmanuel Lhuillier
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Marco Pala
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France.
| | - Abdelkarim Ouerghi
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France.
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6
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Poursoti Z, Sun W, Bharadwaj S, Malac M, Iyer S, Khosravi F, Cui K, Qi L, Nazemifard N, Jagannath R, Rahman R, Jacob Z. Deep ultra-violet plasmonics: exploiting momentum-resolved electron energy loss spectroscopy to probe germanium. OPTICS EXPRESS 2022; 30:12630-12638. [PMID: 35472896 DOI: 10.1364/oe.447017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/15/2022] [Indexed: 06/14/2023]
Abstract
Germanium is typically used for solid-state electronics, fiber-optics, and infrared applications, due to its semiconducting behavior at optical and infrared wavelengths. In contrast, here we show that the germanium displays metallic nature and supports propagating surface plasmons in the deep ultraviolet (DUV) wavelengths, that is typically not possible to achieve with conventional plasmonic metals such as gold, silver, and aluminum. We measure the photonic band spectrum and distinguish the plasmonic excitation modes: bulk plasmons, surface plasmons, and Cherenkov radiation using a momentum-resolved electron energy loss spectroscopy. The observed spectrum is validated through the macroscopic electrodynamic electron energy loss theory and first-principles density functional theory calculations. In the DUV regime, intraband transitions of valence electrons dominate over the interband transitions, resulting in the observed highly dispersive surface plasmons. We further employ these surface plasmons in germanium to design a DUV radiation source based on the Smith-Purcell effect. Our work opens a new frontier of DUV plasmonics to enable the development of DUV devices such as metasurfaces, detectors, and light sources based on plasmonic germanium thin films.
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7
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First-principles Calculations of Optical Energy Loss Functions for 30 Compound and 5 Elemental Semiconductors. E-JOURNAL OF SURFACE SCIENCE AND NANOTECHNOLOGY 2021. [DOI: 10.1380/ejssnt.2021.70] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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8
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He Z, Li Z, Li C, Xue W, Cui W. Ultra-high sensitivity sensing based on ultraviolet plasmonic enhancements in semiconductor triangular prism meta-antenna systems. OPTICS EXPRESS 2020; 28:17595-17610. [PMID: 32679965 DOI: 10.1364/oe.395640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
Silicon (Si), germanium (Ge), and gallium arsenide (GaAs) are familiar semiconductors that always act in the role of optical dielectrics. However, these semiconductors also have plasmonic behaviors in ultraviolet (UV) ranges due to the strong interband transitions or valence electrons. And few studies are aimed at investigating plasmonic properties in the semiconductor at the nanoscale. In this work, we discuss UV plasmonics and sensing properties in single and dimer Si, Ge, and GaAs triangular prism meta-antenna systems. The results show that obvious local surface plasmon resonances (LSPRs) can be realized in the proposed triangular prism meta-antennas, and the resonant wavelength, electromagnetic field distribution, surface charge distribution, and surface current density can be effectively tuned by structural and material parameters. In addition, we also find that the Si triangular prism meta-antenna shows more intense plasmonic responses in UV ranges than that in the Ge or GaAs triangular prism nanostructures. Especially, the phase difference between the triangular prism nanostructure and light source can effectively regulate the symbol and value of the surface charge. Moreover, the great enhancement of electric field can be seen in the dimer triangular prism meta-antennas when the distance of the gap is g<5 nm, especially g=1 nm. The most interesting result is that the maximum of refractive index sensitivity s and figure of merit (FoM) are greatly enlarged in dimer triangular prism meta-antennas. Particularly, the sensitivity can reach up to 215 nm/RIU in the dimer GaAs triangular prism meta-antennas, which is improved more than one order of magnitude. These research results may play important roles in applications of the photo detecting, plasmonic sensing and disinfecting in UV ranges.
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Dong Z, Wang T, Chi X, Ho J, Tserkezis C, Yap SLK, Rusydi A, Tjiptoharsono F, Thian D, Mortensen NA, Yang JKW. Ultraviolet Interband Plasmonics With Si Nanostructures. NANO LETTERS 2019; 19:8040-8048. [PMID: 31560545 DOI: 10.1021/acs.nanolett.9b03243] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Although Si acts as an electrical semiconductor, it has properties of an optical dielectric. Here, we revisit the behavior of Si as a plasmonic metal. This behavior was previously shown to arise from strong interband transitions that lead to negative permittivity of Si across the ultraviolet spectral range. However, few have studied the plasmonic characteristics of Si, particularly in its nanostructures. In this paper, we report localized plasmon resonances of Si nanostructures and the observation of plasmon hybridization in the UV (∼250 nm wavelength). In addition, simulation results show that Si nanodisk dimers can achieve a local intensity enhancement greater than ∼500-fold in a 1 nm gap. Lastly, we investigate hybrid Si-Al nanostructures to achieve sharp resonances in the UV, due to the coupling between plasmon resonances supported by Si and Al nanostructures. These results will have potential applications in the UV range, such as nanostructured devices for spectral filtering, plasmon-enhanced Si photodetectors, interrogation of molecular chirality, and catalysis. It could have significant impact on UV photolithography on patterned Si structures.
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Affiliation(s)
- Zhaogang Dong
- Institute of Materials Research and Engineering , A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, #08-03 Innovis , 138634 Singapore
| | - Tao Wang
- Institute of Materials Research and Engineering , A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, #08-03 Innovis , 138634 Singapore
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices , Soochow University , Suzhou 215123 , Jiangsu , China
| | - Xiao Chi
- Singapore Synchrotron Light Source (SSLS) , National University of Singapore , 5 Research Link , 117603 , Singapore
| | - Jinfa Ho
- Institute of Materials Research and Engineering , A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, #08-03 Innovis , 138634 Singapore
| | - Christos Tserkezis
- Center for Nano Optics , University of Southern Denmark , Campusvej 55 , DK-5230 Odense M , Denmark
| | - Sherry Lee Koon Yap
- Institute of Materials Research and Engineering , A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, #08-03 Innovis , 138634 Singapore
| | - Andrivo Rusydi
- Singapore Synchrotron Light Source (SSLS) , National University of Singapore , 5 Research Link , 117603 , Singapore
- Department of Physics , National University of Singapore , 2 Science Drive 3, 117542 , Singapore
| | - Febiana Tjiptoharsono
- Institute of Materials Research and Engineering , A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, #08-03 Innovis , 138634 Singapore
| | - Dickson Thian
- Institute of Materials Research and Engineering , A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, #08-03 Innovis , 138634 Singapore
| | - N Asger Mortensen
- Center for Nano Optics , University of Southern Denmark , Campusvej 55 , DK-5230 Odense M , Denmark
- Danish Institute for Advanced Study , University of Southern Denmark , Campusvej 55 , DK-5230 Odense M , Denmark
| | - Joel K W Yang
- Institute of Materials Research and Engineering , A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, #08-03 Innovis , 138634 Singapore
- Singapore University of Technology and Design , 8 Somapah Road , 487372 , Singapore
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10
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Jiang Y, Wang X, Pan A. Properties of Excitons and Photogenerated Charge Carriers in Metal Halide Perovskites. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1806671. [PMID: 31106917 DOI: 10.1002/adma.201806671] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 03/01/2019] [Indexed: 05/25/2023]
Abstract
Metal halide perovskites (MHPs) have recently attracted great attention from the scientific community due to their excellent photovoltaic performance as well as their tremendous potential for other optoelectronic applications such as light-emitting diodes, lasers, and photodetectors. Despite the rapid progress in device applications, a solid understanding of the photophysical properties behind the device performance is highly desirable for MHPs. Here, the properties of excitons and photogenerated charge carriers in MHPs are explored. The unique dielectric constant properties, crystal-liquid duality, and fundamental optical processes of MHPs are first discussed. The properties of excitons and related phenomena in MHPs are then detailed, including the exciton binding energy determined by various methods and their influence factors, exciton dynamics, exciton-photon coupling and related applications, and exciton-phonon coupling in MHPs. The properties of photogenerated free charge carriers in MHPs such as the carrier diffusion length, mobility, and recombination are described. Recent progress in various applications is also demonstrated. Finally, a conclusion and perspectives of future studies for MHPs are presented.
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Affiliation(s)
- Ying Jiang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronics, Hunan University, Changsha, 410012, China
| | - Xiao Wang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronics, Hunan University, Changsha, 410012, China
| | - Anlian Pan
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, College of Materials Science and Engineering, Hunan University, Changsha, 410012, China
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11
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Ghosh S, Lu HC, Cho SH, Maruvada T, Price MC, Milliron DJ. Colloidal ReO 3 Nanocrystals: Extra Re d-Electron Instigating a Plasmonic Response. J Am Chem Soc 2019; 141:16331-16343. [PMID: 31533419 DOI: 10.1021/jacs.9b06938] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Rhenium (+6) oxide (ReO3) is metallic in nature, which means it can sustain localized surface plasmon resonance (LSPR) in its nanocrystalline form. Herein, we describe the colloidal synthesis of nanocrystals (NCs) of this compound, through a hot-injection route entailing the reduction of rhenium (+7) oxide with a long chain ether. This synthetic protocol is fundamentally different from the more widely employed nucleophilic lysing of metal alkylcarboxylates for other metal oxide NCs. Owing to this difference, the NC surfaces are populated by ether molecules through an L-type coordination along with covalently bound (X-type) hydroxyl moieties, which enables easy switching from nonpolar to polar solvents without resorting to cumbersome ligand exchange procedures. These as-synthesized NCs exhibit absorption bands at around 590 nm (∼2.1 eV) and 410 nm (∼3 eV), which were respectively ascribed to their LSPR and interband absorptions by Mie theory simulations and Drude modeling. The LSPR response arises from the oscillation of free electron density created by the extra Re d-electron per ReO3 unit in the NC lattice, which resides in the conduction band. Further, the LSPR contribution facilitates the observation of dynamic optical modulation of the NC films as they undergo progressive electrochemical charging via ion (de)insertion. Ion (de)insertion leads to distinct dynamic optical signatures, and these changes are reversible in a wide potential range depending on the choice of the ion (lithium or tetrabutylammonium). Nanostructuring in ReO3 and the description of the associated plasmonic properties of these NCs made this optical modulation feasible, which were hitherto not reported for the bulk material. We envisage that the synthetic protocol described here will facilitate further exploration of such applications and fundamental studies of these plasmonic NCs.
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Affiliation(s)
- Sandeep Ghosh
- McKetta Department of Chemical Engineering , The University of Texas at Austin , Austin , Texas 78712-1589 , United States
| | - Hsin-Che Lu
- McKetta Department of Chemical Engineering , The University of Texas at Austin , Austin , Texas 78712-1589 , United States
| | - Shin Hum Cho
- McKetta Department of Chemical Engineering , The University of Texas at Austin , Austin , Texas 78712-1589 , United States
| | - Thejaswi Maruvada
- McKetta Department of Chemical Engineering , The University of Texas at Austin , Austin , Texas 78712-1589 , United States
| | - Murphie C Price
- McKetta Department of Chemical Engineering , The University of Texas at Austin , Austin , Texas 78712-1589 , United States
| | - Delia J Milliron
- McKetta Department of Chemical Engineering , The University of Texas at Austin , Austin , Texas 78712-1589 , United States
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12
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Meng Q, Xu G, Xin H, Stach EA, Zhu Y, Su D. Quantification of Charge Transfer at the Interfaces of Oxide Thin Films. J Phys Chem A 2019; 123:4632-4637. [PMID: 31050895 DOI: 10.1021/acs.jpca.9b02802] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The interfacial electronic distribution in transition-metal oxide thin films is crucial to their interfacial physical or chemical behaviors. Core-loss electron energy-loss spectroscopy (EELS) may potentially give valuable information of local electronic density of state at high spatial resolution. Here, we studied the electronic properties at the interface of Pb(Zr0.2Ti0.8)O3 (PZT)/4.8 nm La0.8Sr0.2MnO3 (LSMO)/SrTiO3 (STO) using valance-EELS with a scanning transmission electron microscope. Modeled with dielectric function theory, the charge transfer in the vicinity of the interfaces of PZT/LSMO and LSMO/STO was determined from the shifts of plasma peaks of valence EELS (VEELS), agreeing with theoretical prediction. Our work demonstrates that the VEELS method enables a high-efficient quantification of the charge transfer at interfaces, shedding light on the charge-transfer issues at heterogenous interfaces in physical and chemical devices.
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Shinotsuka H, Tanuma S, Powell CJ, Penn DR. Calculations of electron inelastic mean free paths. XII. Data for 42 inorganic compounds over the 50 eV to 200 keV range with the full Penn algorithm. SURF INTERFACE ANAL 2018; 51:427-457. [PMID: 32116395 PMCID: PMC7047655 DOI: 10.1002/sia.6598] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/12/2018] [Indexed: 12/27/2022]
Abstract
We have calculated inelastic mean free paths (IMFPs) for 42 inorganic compounds (AgBr, AgCl, AgI, Al2O3, AlAs, AlN, AlSb, cubic BN, hexagonal BN, CdS, CdSe, CdTe, GaAs, GaN, GaP, GaSb, GaSe, InAs, InP, InSb, KBr, KCl, MgF2, MgO, NaCl, NbC0.712, NbC0.844, NbC0.93, PbS, PbSe, PbTe, SiC, SiO2, SnTe, TiC0.7, TiC0.95, VC0.76, VC0.86, Y3Al5O12, ZnS, ZnSe, and ZnTe) for electron energies from 50 eV to 200 keV. These calculations were made with energy-loss functions (ELFs) obtained from measured optical constants for 15 compounds while calculated ELFs were utilized for the other 27 compounds. Checks based on ELF sum rules showed that the calculated ELFs were superior to the measured ELFs that we had used previously. Our calculated IMFPs could be fitted to a modified form of the relativistic Bethe equation for inelastic scattering of electrons in matter for energies from 50 eV to 200 keV. The average root-mean-square (RMS) deviation in these fits was 0.60 %. The IMFPs were also compared with a relativistic version of our predictive Tanuma-Powell-Penn (TPP-2M) equation. The average RMS deviation in these comparisons was 10.7 % for energies between 50 eV and 200 keV. This average RMS deviation is almost the same as that found in a similar comparison for a group of 41 elemental solids (11.9 %) although relatively large deviations were found for cubic BN (65.6 %) and hexagonal BN (34.3%). If these two compounds are excluded in the comparisons, the average RMS deviation becomes 8.7 %. We found generally satisfactory agreement between our calculated IMFPs and values from other calculations and from experiments.
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Affiliation(s)
- Hiroshi Shinotsuka
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Shigeo Tanuma
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Cedric J. Powell
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Dave R. Penn
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
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14
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Yang JY, Hu M. Temperature-Induced Large Broadening and Blue Shift in the Electronic Band Structure and Optical Absorption of Methylammonium Lead Iodide Perovskite. J Phys Chem Lett 2017; 8:3720-3725. [PMID: 28753018 DOI: 10.1021/acs.jpclett.7b01719] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The power conversion efficiency of hybrid halide perovskite solar cells is profoundly influenced by the operating temperature. Here we investigate the temperature influence on the electronic band structure and optical absorption of cubic CH3NH3PbI3 from first-principles by accounting for both the electron-phonon interaction and thermal expansion. Within the framework of density functional perturbation theory, the electron-phonon coupling induces slightly enlarged band gap and strongly broadened electronic relaxation time as temperature increases. The large broadening effect is mainly due to the presence of cation organic atoms. Consequently, the temperature-dependent absorption peak exhibits blue-shift position, decreased amplitude, and broadened width. This work uncovers the atomistic origin of temperature influence on the optical absorption of cubic CH3NH3PbI3 and can provide guidance to design high-performance hybrid halide perovskite solar cells at different operating temperatures.
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Affiliation(s)
- Jia-Yue Yang
- Institute of Mineral Engineering, Division of Material Science and Engineering, Faculty of Georesources and Materials Engineering, RWTH Aachen University , 52064 Aachen, Germany
| | - Ming Hu
- Institute of Mineral Engineering, Division of Material Science and Engineering, Faculty of Georesources and Materials Engineering, RWTH Aachen University , 52064 Aachen, Germany
- Aachen Institute of Advanced Study in Computational Engineering Science (AICES), RWTH Aachen University , 52062 Aachen, Germany
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15
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Wang K, Wang G, Chang B, Tran H, Fu R. Temperature dependence of photoemission characteristics from Al xGa 1-xAs/GaAs photocathodes. APPLIED OPTICS 2017; 56:6015-6021. [PMID: 29047924 DOI: 10.1364/ao.56.006015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 06/24/2017] [Indexed: 06/07/2023]
Abstract
In this work, photon-enhanced thermionic emission (PETE), which simultaneously harvests solar photonic and thermionic energies, is studied theoretically and experimentally with a transmission-mode AlxGa1-xAs/GaAs cathode within a compact photodiode. The effect of temperature on energy distribution and photoemission yield was experimentally studied in the wavelength range 450-850 nm. The variation of the energy distribution with increasing temperatures demonstrates that direct photoemission gradually declines, while PETE contribution increases with increased heat. Further quantitative proof of the PETE phenomenon can be observed at 850 nm, as temperature increases from 20°C to 90°C. The PETE model with the t-mode AlxGa1-xAs/GaAs cathode is deduced, and the temperature dependence of electron affinity can be achieved. The results show promising applications of the AlxGa1-xAs/GaAs cathode in combined solar/thermal energy conversion.
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16
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Zandi O, Wilkin KJ, Centurion M. Implementation and modeling of a femtosecond laser-activated streak camera. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:063305. [PMID: 28667974 DOI: 10.1063/1.4985008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A laser-activated streak camera was built to measure the duration of femtosecond electron pulses. The streak velocity of the device is 1.89 mrad/ps, which corresponds to a sensitivity of 34.9 fs/pixels. The streak camera also measures changes in the relative time of arrival between the laser and electron pulses with a resolution of 70 fs RMS. A full circuit analysis of the structure is presented to describe the streaking field and the general behavior of the device. We have developed a general mathematical model to analyze the streaked images. The model provides an accurate method to extract the pulse duration based on the changes of the electron beam profile when the streaking field is applied.
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Affiliation(s)
- O Zandi
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - K J Wilkin
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - M Centurion
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
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17
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Sohrabi L, Boochani A, Sebt SA, Elahi SM. Structural, Electronic and Optical Properties of InAs Phases: By GGA-PBG and GGA-EV Approximations. JOURNAL OF CHEMICAL RESEARCH 2017. [DOI: 10.3184/174751917x14873588907648] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Structural, electronic and optical properties of InAs are investigated in the zinc-blende (ZB), rock-salt (RS) and wurtzite (WZ) phases using the full potential linearised augmented plane wave method in the framework of density functional theory (DFT). The electronic band gap of the ZB and WZ phases are improved and in good agreement with experiments by GGA-EV approximation. This compound has a direct band gap in the ZB and WZ phases in point at the centre Brillouin zone and in the RS phase the conduction band crosses towards the valence band and has metallic behaviour. Also, the optical parameters such as the real and imaginary parts of epsilon, energy loss, and the refraction and reflection indices of all the phases are calculated and compared. The calculated optical properties of InAs have promising applications such as the design of optoelectronic and photonic devices.
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Affiliation(s)
- Leila Sohrabi
- Department of Physics, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Arash Boochani
- Department of Physics, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran
| | - S. Ali Sebt
- Department of Physics, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - S. Mohammad Elahi
- Department of Physics, Science and Research Branch, Islamic Azad University, Tehran, Iran
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18
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Zhao D, Gao N, Jia R, Zhang L, Yan W, Liu D. Photoresistless fabrication of periodic patterns on GaAs by laser interference photochemical lithography. RSC Adv 2016. [DOI: 10.1039/c6ra07093k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SEM images of (a) two-beam and (b) three-beam interference patterns formed on GaAs wafers by photochemical etching with an incident angle of 17°.
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Affiliation(s)
- Dongfang Zhao
- State Key Laboratory of Crystal Materials
- Shandong University
- Jinan
- P. R. China
| | - Naikun Gao
- State Key Laboratory of Crystal Materials
- Shandong University
- Jinan
- P. R. China
| | - Ran Jia
- State Key Laboratory of Crystal Materials
- Shandong University
- Jinan
- P. R. China
| | - Ling Zhang
- State Key Laboratory of Crystal Materials
- Shandong University
- Jinan
- P. R. China
| | - Weishan Yan
- State Key Laboratory of Crystal Materials
- Shandong University
- Jinan
- P. R. China
| | - Duo Liu
- State Key Laboratory of Crystal Materials
- Shandong University
- Jinan
- P. R. China
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19
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Iida K, Noda M, Nobusada K. Control of optical response of a supported cluster on different dielectric substrates. J Chem Phys 2015; 142:214702. [PMID: 26049511 DOI: 10.1063/1.4921840] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
We develop a computational method for optical response of a supported cluster on a dielectric substrate. The substrate is approximated by a dielectric continuum with a frequency-dependent dielectric function. The computational approach is based on our recently developed first-principles simulation method for photoinduced electron dynamics in real-time and real-space. The approach allows us to treat optical response of an adsorbate explicitly taking account of interactions at an interface between an adsorbate and a substrate. We calculate optical absorption spectra of supported Agn (n = 2, 54) clusters, changing the dielectric function of a substrate. By analyzing electron dynamics in real-time and real-space, we clarify the mechanisms for variations in absorption spectra, such as peak shifts and intensity changes, relating to various experimental results for optical absorption of supported clusters. Attractive and repulsive interactions between an adsorbate and a substrate result in red and blue shifts, respectively, and the intensity decreases by energy dissipation into a substrate. We demonstrate that optical properties can be controlled by varying the dielectric function of a substrate.
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Affiliation(s)
- Kenji Iida
- Department of Theoretical and Computational Molecular Science, Institute for Molecular Science, Okazaki 444-8585, Japan
| | - Masashi Noda
- Department of Theoretical and Computational Molecular Science, Institute for Molecular Science, Okazaki 444-8585, Japan
| | - Katsuyuki Nobusada
- Department of Theoretical and Computational Molecular Science, Institute for Molecular Science, Okazaki 444-8585, Japan
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20
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Ferrari AM, Orlando R, Rérat M. Ab Initio Calculation of the Ultraviolet–Visible (UV-vis) Absorption Spectrum, Electron-Loss Function, and Reflectivity of Solids. J Chem Theory Comput 2015; 11:3245-58. [DOI: 10.1021/acs.jctc.5b00199] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anna Maria Ferrari
- Dipartimento
di Chimica IFM, Università di Torino and Nanostructured Interfaces and Surfaces (NIS)—Centre of Excellence , Via P. Giuria 7, 10125 Torino, Italy
| | - Roberto Orlando
- Dipartimento
di Chimica IFM, Università di Torino and Nanostructured Interfaces and Surfaces (NIS)—Centre of Excellence , Via P. Giuria 7, 10125 Torino, Italy
| | - Michel Rérat
- Equipe
de Chimie
Physique, IPREM UMR5254, Université de Pau et des Pays de l’Adour, 64000 Pau, France
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21
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Mechanical, electronic, and optical properties of Bi2S3 and Bi2Se3 compounds: first principle investigations. J Mol Model 2014; 20:2180. [DOI: 10.1007/s00894-014-2180-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 02/11/2014] [Indexed: 10/25/2022]
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22
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Oxygen doped SiC nanocrystals: first principles study of the optical properties. J Mol Model 2013; 19:3603-10. [PMID: 23743607 DOI: 10.1007/s00894-013-1895-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 05/21/2013] [Indexed: 10/26/2022]
Abstract
We have studied a typical spherical SiC nanocrystal with a diameter of 1.2 nm (Si43C44H76) using linear combination of atomic orbitals in combination with pesudopotential density functional calculation. The role of fluorine and oxygen impurities was investigated on the electronic and optical properties of the Si43C44H76 nanocrystal. Total energy calculations show that the fluorine doped Si43C44H76 nanocrystals are unstable. Oxygen doped Si43C44H76 have different binding energies in various substitutional and interstitial defects. The maximum binding energy of the oxygen at carbon substitutional defect is about -0.5 eV and at interstitial defect is -0.18 eV. The HOMO-LUMO gap of the pure Si43C44H76 is about 6.71 eV and after doping with oxygen changes on the order of 0.1 eV. Our studies show that the refractive index of the doped Si43C44H76 nanocrystal significantly dispersed in comparison with pure SiC nanocrystal especially at the range of 6 to 8 eV.
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23
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Lischner J, Vigil-Fowler D, Louie SG. Physical origin of satellites in photoemission of doped graphene: an ab initio GW plus cumulant study. PHYSICAL REVIEW LETTERS 2013; 110:146801. [PMID: 25167020 DOI: 10.1103/physrevlett.110.146801] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2012] [Indexed: 05/26/2023]
Abstract
We calculate the photoemission spectra of suspended and epitaxial doped graphene using an ab initio cumulant expansion of the Green's function based on the GW self-energy. Our results are compared to experiment and to standard GW calculations. For doped graphene on a silicon carbide substrate, we find, in contrast to earlier calculations, that the spectral function from GW only does not reproduce experimental satellite properties. However, ab initio GW plus cumulant theory combined with an accurate description of the substrate screening results in good agreement with experiment, but gives no plasmaron (i.e., no extra well-defined excitation satisfying Dyson's equation).
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Affiliation(s)
- Johannes Lischner
- Department of Physics, University of California, Berkeley, California 94720, USA and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Derek Vigil-Fowler
- Department of Physics, University of California, Berkeley, California 94720, USA and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Steven G Louie
- Department of Physics, University of California, Berkeley, California 94720, USA and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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24
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Optical properties of GaAs nanocrystals: influence of an electric field. J Mol Model 2013; 19:2273-83. [PMID: 23377958 DOI: 10.1007/s00894-013-1753-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 01/02/2013] [Indexed: 10/27/2022]
Abstract
A study of the electronic and optical properties of the hydrogen-terminated GaAs nanocrystals Ga₆₈As₆₈H₉₆ and Ga₉₂As₈₀H₁₀₈ is presented. In this study, their dielectric functions, refractive indices, and absorption coefficients were calculated using density functional theory (DFT). The influence of a uniform external electric field on the optical properties of the nanocrystals was also explored. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) for each nanocrystal were studied in the absence and the presence of the uniform external electric field. Our results indicate that the HOMO-LUMO gap decreases with increasing electric field strength. The calculated density of states revealed that the main reason for this shrinking gap is an increase in the delocalization of the gallium π-orbitals under the influence of an increasing external electric field. The permanent dipole moment and the polarizability of the nanocrystals under the induced electric field increased with increasing nanocrystal radius. The induced electric field caused a noticeable redshift in the absorption peaks. The electric field also increased the absorption intensity, particularly when the field strength was >0.25 V/Å.
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25
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Tisone GC, Wayne Johnson A. Laser-Controlled Etching Of Chromium-Doped and N-Doped <100> Gaas. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-17-73] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTThe photochemical etching of chromium-doped and n-doped <100> GaAs in HNO3 and KOH is examined in the wavelength region of 334 to 514 nm from an argon-ion laser. The etching process is found to be not thermally controlled. The etch rates of chromium-doped GaAs agree with a diffusion-controlled model of the photochemically produced holes. For both types of GaAs, HNO3 is found to produce morphologically superior results.
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26
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Kinyanjui MK, Axmann P, Wohlfahrt-Mehrens M, Moreau P, Boucher F, Kaiser U. Origin of valence and core excitations in LiFePO(4) and FePO(4). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:275501. [PMID: 21399256 DOI: 10.1088/0953-8984/22/27/275501] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Electronic structures of LiFePO(4) and FePO(4) have been investigated using valence and core electron energy loss spectroscopy (EELS) supported by ab initio calculations. Valence electron energy loss spectra of FePO(4) are characterized by interband transitions found between 0 and 20 eV, which are not observed in LiFePO(4). Spectra are fully analysed using band structure calculations and calculated dielectric functions. In particular, we show that interband transitions observed in FePO(4) spectra originate from the states at the top of the valence band, which have mainly oxygen p character. From core-loss EELS, it is observed that the O-K edge in FePO(4) has a pre-edge peak below the threshold of the main O-K edge. This pre-edge peak is not observed in the O-K spectra of LiFePO(4). The position of the pre-edge peak is determined by a charge transfer process, which shifts the position of the iron 3d bands with respect to the conduction band. The intensity of the pre-edge peak is also determined by the changes in the hybridization of iron 3d and oxygen states as a result of extraction of lithium ions from the LiFePO(4) lattice. We show that the extraction of lithium ions from LiFePO(4) results in large changes in the electronic structure, such that FePO(4) can be considered to be a charge transfer insulator while LiFePO(4) is a typical Mott-Hubbard insulator.
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Affiliation(s)
- M K Kinyanjui
- University of Ulm, Albert Einstein Allee 11, 89081 Ulm, Germany.
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27
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Perevalov T, Gritsenko V. Application and electronic structure of high-permittivity dielectrics. ACTA ACUST UNITED AC 2010. [DOI: 10.3367/ufnr.0180.201006b.0587] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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28
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Erdinc B, Akkus H. Electronic band structure and linear optical properties of paraelectric KIO(3). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:125503. [PMID: 21817468 DOI: 10.1088/0953-8984/21/12/125503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The electronic energy band structure, partial (PDOS) and total density of states (DOS), and linear optical properties of the paraelectric KIO(3) single crystal are calculated using density functional theory (DFT) in its local density approximation (LDA). The calculated band structure for paraelectric KIO(3) indicates that the crystal has a direct bandgap. Using LDA and generalized gradient approximation (GGA), structural optimization has been performed. The optical spectra of the paraelectric KIO(3) in the photon energy range up to 30 eV are investigated under the scissor approximation. The real and imaginary parts of the frequency-dependent linear dielectric function, as well as related quantities such as energy-loss function, refractive index and effective number of valence electrons, are calculated. The calculated structural optimization and bandgap of the paraelectric KIO(3) have been compared with experimental data and have been found to be in good agreement with the experimental results.
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29
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Long Range Cooperative and Local Jahn-Teller Effects in Nanocrystalline Transition Metal Thin Films. SPRINGER SERIES IN CHEMICAL PHYSICS 2009. [DOI: 10.1007/978-3-642-03432-9_24] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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30
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Stöger-Pollach M. Optical properties and bandgaps from low loss EELS: Pitfalls and solutions. Micron 2008; 39:1092-110. [DOI: 10.1016/j.micron.2008.01.023] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Revised: 01/31/2008] [Accepted: 01/31/2008] [Indexed: 11/24/2022]
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31
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Low energy electron-excited nanoscale luminescence spectroscopy studies of intrinsic defects in HfO[sub 2] and SiO[sub 2]–HfO[sub 2]–SiO[sub 2]–Si stacks. ACTA ACUST UNITED AC 2008. [DOI: 10.1116/1.2830692] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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32
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Synchrotron radiation as a light source. ACTA ACUST UNITED AC 2007. [DOI: 10.1007/bfb0107300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
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33
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Electron Emission Physics. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s1076-5670(07)49004-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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34
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Affiliation(s)
- Marie-Luce Theye
- a Laboratoire d'Optique des Solides, UA CNRS no. 781 , Université P. et M. Curie , 4 Place Jussieu, 75230 , Paris Cedex 05 , France
| | - Adriana Gheorghiu
- a Laboratoire d'Optique des Solides, UA CNRS no. 781 , Université P. et M. Curie , 4 Place Jussieu, 75230 , Paris Cedex 05 , France
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35
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Osgood R. Photoreaction Dynamics of Molecular Adsorbates on Semiconductor and Oxide Surfaces. Chem Rev 2006; 106:4379-401. [PMID: 17031991 DOI: 10.1021/cr050175x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Richard Osgood
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA
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36
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Gheorghiu A, Thèye ML. Disorder effects and the optical properties of amorphous GaAs and GaP. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01418638108222561] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Adriana Gheorghiu
- a Laboratoire d'Optique des Solides† , Université Pierre et Marie Curie , 4 place Jussieu, 75230 , Paris , Cédex 05 , France
| | - Marie-Luce Thèye
- a Laboratoire d'Optique des Solides† , Université Pierre et Marie Curie , 4 place Jussieu, 75230 , Paris , Cédex 05 , France
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37
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Ewald D, Milleville M, Weiser G. Optical spectra of glow-discharge-deposited silicon. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01418637908227168] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- D. Ewald
- a Fachbereich Physik der Philipps-Universität , Marburg , F.R. Germany
| | - M. Milleville
- a Fachbereich Physik der Philipps-Universität , Marburg , F.R. Germany
| | - G. Weiser
- a Fachbereich Physik der Philipps-Universität , Marburg , F.R. Germany
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38
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Fabrication of ultrathin (∼100 nm), low-index nanoporous silica films for photonic devices: Role of substrate adhesion on the film thickness. ACTA ACUST UNITED AC 2006. [DOI: 10.1116/1.2187999] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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39
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Nevo I, Aloni S, Cohen SR, Hasse G. The effect of adsorbed oxygen on the surface potential of n-GaAs(110). J Chem Phys 2005; 123:64705. [PMID: 16122333 DOI: 10.1063/1.1997127] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Potential variations on semiconductor surfaces are often mapped using a combination of constant current topographic and local surface photo-voltage (SPV) imaging. SPV imaging provides a direct measurement of surface-potential variations at large lateral distances from a charged defect or adsorbate. However, directly above the defect, variations in the SPV signal need to be interpreted in terms of surface screening, traps, and band bending. We have examined these effects using isolated oxygen atoms on a GaAS(110) surface, which is free of surface states. We interpret variations in the SPV signal in terms of a simple electrostatic model which considers the oxygen-induced Coulomb potential and corresponding image potential, both of which affect the surface density of states.
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Affiliation(s)
- Iftach Nevo
- Weizmann Institute of Science, Rehovot Israel 76100
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Lazar S, Botton GA, Wu MY, Tichelaar FD, Zandbergen HW. Materials science applications of HREELS in near edge structure analysis and low-energy loss spectroscopy. Ultramicroscopy 2003; 96:535-46. [PMID: 12871814 DOI: 10.1016/s0304-3991(03)00114-1] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
New experiments made possible with a commercial transmission electron microscope (TEM) equipped with a high-resolution electron energy loss spectrometer (EELS) are presented. With this commercial system, a 100 meV energy resolution using a sub 2 nm probe or 500 meV at a 0.20 nm probe are possible, in combination with other modern techniques available for TEMs. In this paper a number of explorative examples of the first results are shown. The benefit of the increased resolution for detecting more details in near edge structures are shown for the Ti K edge in TiO(2) (brookite) and for the N K edge in cubic and hexagonal GaN. The bandgap of GaN is studied in both crystal structures, as well as the dependency of the low-loss spectrum on the momentum transfer direction in diffraction mode.
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Affiliation(s)
- S Lazar
- National Centre for HREM, Department of Technical Sciences, Delft University of Technology, Laboratory for Materials Science, Rotterdamseweg 137, Delft 2628 AL, The Netherlands
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Thirlwell J. The characteristic energy losses of slow electrons reflected from aluminium, germanium, copper and gold. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0370-1328/91/3/305] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Roessler DM. Kramers - Kronig analysis of reflectance data: III. Approximations, with reference to sodium iodide. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0508-3443/17/10/309] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Nagao T, Hildebrandt T, Henzler M, Hasegawa S. Dispersion and damping of a two-dimensional plasmon in a metallic surface-state band. PHYSICAL REVIEW LETTERS 2001; 86:5747-5750. [PMID: 11415348 DOI: 10.1103/physrevlett.86.5747] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2000] [Indexed: 05/23/2023]
Abstract
We have studied, for the first time, the energy and the linewidth dispersion of a plasmon in a dense two-dimensional electron system in a metallic surface-state band on a silicon surface. As expected from the considerably high effective density and long Fermi wavelength of the system, the plasmon energy dispersion exhibited an excellent agreement with the nearly free-electron theory. However, in a small wave number region below the Landau edge, we have observed an anomalous linewidth dispersion which nearly free-electron theories do not predict.
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Affiliation(s)
- T Nagao
- Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Grasso V, Mondio G, Saitta G. Optical constants of MoTe2from reflectivity measurements. (Brillouin zone transitions). ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/5/10/015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Misell DL, Crick RA. The energy loss of fast electrons in evaporated amorphous films of germanium for the spectral region 2-50 eV. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/4/12/017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Leigh RS, Szigeti B. Raman and photoelastic constants and impurity absorption in valency crystals. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/3/4/006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Inkson JC. Many-body effects at metal-semiconductor junctions. I. Surface plasmons and the electron-electron screened interaction. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/5/18/010] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Thutupalli GKM, Tomlin SG. The optical properties of amorphous and crystalline silicon. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/10/3/017] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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