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dos Reis JRT, Leite FF, Sharma K, Ribeiro GAS, Silva WHN, Batista AA, Paschoal AR, Paraguassu W, Mazzoni M, Barbosa Neto NM, Araujo PT. Raman Spectroscopy on Free-Base Meso-tetra(4-pyridyl) Porphyrin under Conditions of Low Temperature and High Hydrostatic Pressure. Molecules 2024; 29:2362. [PMID: 38792223 PMCID: PMC11124280 DOI: 10.3390/molecules29102362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/01/2024] [Accepted: 04/02/2024] [Indexed: 05/26/2024] Open
Abstract
We present a Raman spectroscopy study of the vibrational properties of free-base meso-tetra(4-pyridyl) porphyrin polycrystals under various temperature and hydrostatic pressure conditions. The combination of experimental results and Density Functional Theory (DFT) calculations allows us to assign most of the observed Raman bands. The modifications in the Raman spectra when excited with 488 nm and 532 nm laser lights indicate that a resonance effect in the Qy band is taking place. The pressure-dependent results show that the resonance conditions change with increasing pressure, probably due to the shift of the electronic transitions. The temperature-dependent results show that the relative intensities of the Raman modes change at low temperatures, while no frequency shifts are observed. The experimental and theoretical analysis presented here suggest that these molecules are well represented by the C2v point symmetry group.
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Affiliation(s)
- Jhon Rewllyson Torres dos Reis
- Graduate Program in Physics, Institute of Natural Sciences, Federal University of Pará, Belém 66075-110, PA, Brazil; (J.R.T.d.R.); (F.F.L.); (W.P.)
| | - Fabio Furtado Leite
- Graduate Program in Physics, Institute of Natural Sciences, Federal University of Pará, Belém 66075-110, PA, Brazil; (J.R.T.d.R.); (F.F.L.); (W.P.)
- Department of Exact and Technological Sciences, Federal University of Amapá, Macapá 68903-419, AP, Brazil
| | - Keshav Sharma
- Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487, USA;
| | - Guilherme Almeida Silva Ribeiro
- Department of Physics, Federal University of Minas Gerais, Belo Horizonte 31270-901, MG, Brazil; (G.A.S.R.); (W.H.N.S.); (M.M.)
| | | | - Alzir Azevedo Batista
- Departament of Chemistry, Federal University of São Carlos, São Carlos 13565-905, SP, Brazil;
| | | | - Waldeci Paraguassu
- Graduate Program in Physics, Institute of Natural Sciences, Federal University of Pará, Belém 66075-110, PA, Brazil; (J.R.T.d.R.); (F.F.L.); (W.P.)
| | - Mario Mazzoni
- Department of Physics, Federal University of Minas Gerais, Belo Horizonte 31270-901, MG, Brazil; (G.A.S.R.); (W.H.N.S.); (M.M.)
| | - Newton Martins Barbosa Neto
- Graduate Program in Physics, Institute of Natural Sciences, Federal University of Pará, Belém 66075-110, PA, Brazil; (J.R.T.d.R.); (F.F.L.); (W.P.)
| | - Paulo Trindade Araujo
- Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487, USA;
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2
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Kowalczyk H, Biscaras J, Pistawala N, Harnagea L, Singh S, Shukla A. Gate and Temperature Driven Phase Transitions in Few-Layer MoTe 2. ACS NANO 2023; 17:6708-6718. [PMID: 36972180 DOI: 10.1021/acsnano.2c12610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
MoTe2 has a stable hexagonal semiconducting phase (2H) as well as two semimetallic phases with monoclinic (1T') and orthorhombic (Td) structures. A structural change can thus be accompanied by a significant change in electronic transport properties. The two semimetallic phases are connected by a temperature driven transition and could exhibit topological properties. Here we make extensive Raman measurements as a function of layer thickness, temperature, and electrostatic doping on few layer 2H-MoTe2 and also on 1T'-MoTe2 and Td-WTe2. Recent work in MoTe2 has raised the possibility of a 2H-1T' transition through technology compatible pathways. It has been claimed that such a transition, of promise for device applications, is activated by electrostatic gating. We investigate this claim and find that few-layer tellurides are characterized by high mobility of Te ions, even in ambient conditions and especially through the variation of external parameters like electric field or temperature. These can generate Te clusters, vacancies at crystalline sites, and facilitate structural transitions. We however find that the purported 2H-1T' transition in MoTe2 cannot be obtained by a pure electrostatic field.
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Affiliation(s)
- Hugo Kowalczyk
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, 75005 Paris, France
| | - Johan Biscaras
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, 75005 Paris, France
| | - Nashra Pistawala
- Department of Physics, Indian Institute of Science Education and Research, Pune, Maharashtra 411008, India
| | - Luminita Harnagea
- Department of Physics, Indian Institute of Science Education and Research, Pune, Maharashtra 411008, India
| | - Surjeet Singh
- Department of Physics, Indian Institute of Science Education and Research, Pune, Maharashtra 411008, India
| | - Abhay Shukla
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, 75005 Paris, France
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3
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Jiang B, Wang W, Liu S, Wang Y, Wang C, Chen Y, Xie L, Huang M, He J. High figure-of-merit and power generation in high-entropy GeTe-based thermoelectrics. Science 2022; 377:208-213. [DOI: 10.1126/science.abq5815] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The high-entropy concept provides extended, optimized space of a composition, resulting in unusual transport phenomena and excellent thermoelectric performance. By tuning electron and phonon localization, we enhanced the figure-of-merit value to 2.7 at 750 kelvin in germanium telluride–based high-entropy materials and realized a high experimental conversion efficiency of 13.3% at a temperature difference of 506 kelvin with the fabricated segmented module. By increasing the entropy, the increased crystal symmetry delocalized the distribution of electrons in the distorted rhombohedral structure, resulting in band convergence and improved electrical properties. By contrast, the localized phonons from the entropy-induced disorder dampened the propagation of transverse phonons, which was the origin of the increased anharmonicity and largely depressed lattice thermal conductivity. We provide a paradigm for tuning electron and phonon localization by entropy manipulation, but we have also demonstrated a route for improving the performance of high-entropy thermoelectric materials.
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Affiliation(s)
- Binbin Jiang
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
- School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Wu Wang
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Shixuan Liu
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yan Wang
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chaofan Wang
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yani Chen
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Lin Xie
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Mingyuan Huang
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Jiaqing He
- Shenzhen Key Laboratory of Thermoelectric Materials, Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and Devices, Southern University of Science and Technology, Shenzhen 518055, China
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4
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Dynamics of ultrafast phase transitions in MgF 2 triggered by laser-induced THz coherent phonons. Sci Rep 2022; 12:6621. [PMID: 35459247 PMCID: PMC9033864 DOI: 10.1038/s41598-022-09815-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/21/2022] [Indexed: 11/12/2022] Open
Abstract
The advent of free-electron lasers opens new routes for experimental high-pressure physics, which allows studying dynamics of condensed matter with femtosecond resolution. A rapid compression, that can be caused by laser-induced shock impact, leads to the cascade of high-pressure phase transitions. Despite many decades of study, a complete understanding of the lattice response to such a compression remains elusive. Moreover, in the dynamical case (in contrast to quasi-static loading) the thresholds of phase transitions can change significantly. Using the third harmonic pump–probe technique combined with molecular dynamics to simulate the terahertz (THz) spectrum, we revealed the dynamics of ultrafast laser-induced phase transitions in MgF2 in all-optical experiment. Tight focusing of femtosecond laser pulse into the transparent medium leads to the generation of sub-TPa shock waves and THz coherent phonons. The laser-induced shock wave propagation drastically displaces atoms in the lattice, which leads to phase transitions. We registered a cascade of ultrafast laser-induced phase transitions (P42/mnm ⇒ Pa-3 ⇒ Pnam) in magnesium fluoride as a change in the spectrum of coherent phonons. The phase transition has the characteristic time of 5–10 ps, and the lifetime of each phase is on the order of 40–60 ps. In addition, phonon density of states, simulated by molecular dynamics, together with third-harmonic time-resolved spectra prove that laser-excited phonons in a bulk of dielectrics are generated by displacive excitation (DECP) mechanism in plasma mediated conditions.
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Martinez P, Blanchet V, Descamps D, Dory JB, Fourment C, Papagiannouli I, Petit S, Raty JY, Noé P, Gaudin J. Sub-Picosecond Non-Equilibrium States in the Amorphous Phase of GeTe Phase-Change Material Thin Films. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2102721. [PMID: 34427368 DOI: 10.1002/adma.202102721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/01/2021] [Indexed: 06/13/2023]
Abstract
The sub-picosecond response of amorphous germanium telluride thin film to a femtosecond laser excitation is investigated using frequency-domain interferometry and ab initio molecular dynamics. The time-resolved measurement of the surface dynamics reveals a shrinkage of the film with a dielectric properties' response faster than 300 fs. The systematic ab initio molecular dynamics simulations in non-equilibrium conditions allow the atomic configurations to be retrieved for ionic temperature from 300 to 1100 K and width of the electron distribution from 0.001 to 1.0 eV. Local order of the structures is characterized by in-depth analysis of the angle distribution, phonon modes, and pair distribution function, which evidence a transition toward a new amorphous electronic excited state close in bonding/structure to the liquid state. The results shed a new light on the optically highly excited states in chalcogenide materials involved in both important processes: phase-change materials in memory devices and ovonic threshold switching phenomenon induced by a static field.
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Affiliation(s)
- Paloma Martinez
- CELIA, Université Bordeaux, CEA, CNRS, UMR 5107, 351 Cours de la Libération, Talence, F-33405, France
| | - Valérie Blanchet
- CELIA, Université Bordeaux, CEA, CNRS, UMR 5107, 351 Cours de la Libération, Talence, F-33405, France
| | - Dominique Descamps
- CELIA, Université Bordeaux, CEA, CNRS, UMR 5107, 351 Cours de la Libération, Talence, F-33405, France
| | - Jean-Baptiste Dory
- Université Grenoble Alpes, CEA, LETI, 17 rue des Martyrs, Grenoble Cedex 9, F-38000, France
| | - Claude Fourment
- CELIA, Université Bordeaux, CEA, CNRS, UMR 5107, 351 Cours de la Libération, Talence, F-33405, France
- CEA-CESTA, 15 avenue des Sablières, CS 60001, Le Barp CEDEX, F-33116, France
| | - Irène Papagiannouli
- CELIA, Université Bordeaux, CEA, CNRS, UMR 5107, 351 Cours de la Libération, Talence, F-33405, France
| | - Stéphane Petit
- CELIA, Université Bordeaux, CEA, CNRS, UMR 5107, 351 Cours de la Libération, Talence, F-33405, France
| | - Jean-Yves Raty
- Université Grenoble Alpes, CEA, LETI, 17 rue des Martyrs, Grenoble Cedex 9, F-38000, France
- FRS-FNRS and CESAM, University of Liège, Allée du 6 Août 19, Sart-Tilman, 4000, Belgium
| | - Pierre Noé
- Université Grenoble Alpes, CEA, LETI, 17 rue des Martyrs, Grenoble Cedex 9, F-38000, France
| | - Jérôme Gaudin
- CELIA, Université Bordeaux, CEA, CNRS, UMR 5107, 351 Cours de la Libération, Talence, F-33405, France
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6
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Zhang K, Xu M, Li N, Xu M, Zhang Q, Greenberg E, Prakapenka VB, Chen YS, Wuttig M, Mao HK, Yang W. Superconducting Phase Induced by a Local Structure Transition in Amorphous Sb_{2}Se_{3} under High Pressure. PHYSICAL REVIEW LETTERS 2021; 127:127002. [PMID: 34597067 DOI: 10.1103/physrevlett.127.127002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 07/05/2021] [Accepted: 08/13/2021] [Indexed: 06/13/2023]
Abstract
Superconductivity and Anderson localization represent two extreme cases of electronic behavior in solids. Surprisingly, these two competing scenarios can occur in the same quantum system, e.g., in an amorphous superconductor. Although the disorder-driven quantum phase transition has attracted much attention, its structural origins remain elusive. Here, we discovered an unambiguous correlation between superconductivity and density in amorphous Sb_{2}Se_{3} at high pressure. Superconductivity first emerges in the high-density amorphous (HDA) phase at about 24 GPa, where the density of glass unexpectedly exceeds its crystalline counterpart, and then shows an enhanced critical temperature when pressure induces crystallization at 51 GPa. Ab initio simulations reveal that the bcc-like local geometry motifs form in the HDA phase, arising from distinct "metavalent bonds." Our results demonstrate that HDA phase is critical for the incipient superconductive behavior.
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Affiliation(s)
- Kai Zhang
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203, People's Republic of China
| | - Ming Xu
- Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Nana Li
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203, People's Republic of China
| | - Meng Xu
- Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Qian Zhang
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203, People's Republic of China
| | - Eran Greenberg
- Center for Advanced Radiation Sources, University of Chicago, Chicago, Illinois, USA
| | - Vitali B Prakapenka
- Center for Advanced Radiation Sources, University of Chicago, Chicago, Illinois, USA
| | - Yu-Sheng Chen
- NSF's ChemMatCARS, University of Chicago, Chicago, Illinois 60637, USA
| | - Matthias Wuttig
- Institute of Physics IA, RWTH Aachen University, 52074 Aachen, Germany
| | - Ho-Kwang Mao
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203, People's Republic of China
| | - Wenge Yang
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203, People's Republic of China
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7
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Wang Y, Wang K, Ma Y, Zhou M, Wang H, Liu G. Pressure-induced structural transitions between successional superconducting phases in GeTe. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:355403. [PMID: 34139674 DOI: 10.1088/1361-648x/ac0c3a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 06/17/2021] [Indexed: 06/12/2023]
Abstract
Being a best-known prototype of phase-change materials, GeTe was reported to possess many high-pressure phases, whose structural evolution and superconductivity remain under debate for decades. Herein, we systematically investigated the pressure dependence of electrical transport and the structural evolution of the GeTe viain situangle-dispersive synchrotron x-ray diffraction and resistance measurements up to 55 GPa. At room temperature, the structural phase transitions from the initial rhombohedral phase to theFm3̄mphase, and then to an orthorhombicPnmaphase, were observed at pressures of about 4 and 13.4 GPa, respectively. Furthermore, the metallization occurred at around 11 GPa, where the superconductivity could also be observed. With increasing pressure, the superconducting transition temperature increases monotonically from 5.7 to 6.4 K and then is independent of pressure above 23 GPa in the purePnmaphase. These results provide insights into the pressure-dependent evolution of the structure and superconductivity in GeTe and have implications for the understanding of other IV-VI semiconductors at high pressure.
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Affiliation(s)
- Yingying Wang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, People's Republic of China
| | - Kui Wang
- International Center of Computational Method & Software, College of Physics, Jilin University, Changchun 130012, People's Republic of China
| | - Yanmei Ma
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, People's Republic of China
| | - Mi Zhou
- International Center of Computational Method & Software, College of Physics, Jilin University, Changchun 130012, People's Republic of China
| | - Hongbo Wang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, People's Republic of China
- International Center of Computational Method & Software, College of Physics, Jilin University, Changchun 130012, People's Republic of China
| | - Guangtao Liu
- International Center of Computational Method & Software, College of Physics, Jilin University, Changchun 130012, People's Republic of China
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8
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Singh K, Kumari S, Singh H, Bala N, Singh P, Kumar A, Thakur A. A review on GeTe thin film-based phase-change materials. APPLIED NANOSCIENCE 2021. [DOI: 10.1007/s13204-021-01911-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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9
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Longuinhos R, Vymazalová A, Cabral AR, Ribeiro-Soares J. Raman spectrum of layered tilkerodeite (Pd 2HgSe 3) topological insulator: the palladium analogue of jacutingaite (Pt 2HgSe 3). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:065401. [PMID: 33086198 DOI: 10.1088/1361-648x/abc35a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The layered mineral tilkerodeite (Pd2HgSe3), the palladium analogue of jacutingaite (Pt2HgSe3), is a promising quantum spin hall insulator for low-power nanospintronics. In this context, a fast and reliable assessment of its structure is key for exploring fundamental properties and architecture of new Pd2HgSe3-based devices. Here, we investigate the first-order Raman spectrum in high-quality, single-crystal bulk tilkerodeite, and analyze the wavenumber relation to its isostructural jacutingaite analogue. By using polarized Raman spectroscopy, symmetry analysis, and first-principles calculations, we assigned all the Raman-active phonons in tilkerodeite, unveiling their wavenumbers, atomic displacement patterns, and symmetries. Our calculations used several exchange-correlation functionals within the density functional perturbation theory framework, reproducing both structure and Raman-active phonon wavenumbers in excellent agreement with experiments. Also, it was found that the influence of the spin-orbit coupling can be neglected in the study of these properties. Finally, we compared the wavenumber and atomic displacement patterns of corresponding Raman-active modes in tilkerodeite and jacutingaite, and found that the effect of the Pd and Pt masses can be neglected on reasoning their wavenumber differences. From this analysis, tilkerodeite is found to be mechanically weaker than jacutingaite against the atomic displacement patterns of these modes. Our findings advance the understanding of the structural properties of a recently discovered layered topological insulator, fundamental to further exploring its electronic, optical, thermal, and mechanical properties, and for device fabrication.
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Affiliation(s)
- R Longuinhos
- Departamento de Física, Universidade Federal de Lavras, Lavras, MG, 37200-000, Brazil
| | - A Vymazalová
- Department of Rock Geochemistry, Czech Geological Survey, Geologická 6, 152 00 Prague 5, Czech Republic
| | - A R Cabral
- Centro de Pesquisa Professor Manoel Teixeira da Costa, Instituto de Geociências, Universidade Federal de Minas Gerais (UFMG), 31270-901 Belo Horizonte, MG, Brazil
- Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), 31270-901 Belo Horizonte, MG, Brazil
| | - J Ribeiro-Soares
- Departamento de Física, Universidade Federal de Lavras, Lavras, MG, 37200-000, Brazil
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10
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Flux periodic oscillations and phase-coherent transport in GeTe nanowire-based devices. Nat Commun 2021; 12:754. [PMID: 33531502 PMCID: PMC7854721 DOI: 10.1038/s41467-021-21042-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 01/05/2021] [Indexed: 11/09/2022] Open
Abstract
Despite the fact that GeTe is known to be a very interesting material for applications in thermoelectrics and for phase-change memories, the knowledge on its low-temperature transport properties is only limited. We report on phase-coherent phenomena in the magnetotransport of GeTe nanowires. From universal conductance fluctuations measured on GeTe nanowires with Au contacts, a phase-coherence length of about 280 nm at 0.5 K is determined. The distinct phase-coherence is confirmed by the observation of Aharonov-Bohm type oscillations for parallel magnetic fields. We interpret the occurrence of these magnetic flux-periodic oscillations by the formation of a tubular hole accumulation layer. For Nb/GeTe-nanowire/Nb Josephson junctions we obtained a critical current of 0.2 μA at 0.4 K. By applying a perpendicular magnetic field the critical current decreases monotonously with increasing field, whereas in a parallel field the critical current oscillates with a period of the magnetic flux quantum confirming the presence of a tubular hole channel.
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11
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Meng X, Singh A, Juneja R, Zhang Y, Tian F, Ren Z, Singh AK, Shi L, Lin JF, Wang Y. Pressure-Dependent Behavior of Defect-Modulated Band Structure in Boron Arsenide. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2001942. [PMID: 33015896 DOI: 10.1002/adma.202001942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 09/02/2020] [Indexed: 06/11/2023]
Abstract
The recent observation of unusually high thermal conductivity exceeding 1000 W m-1 K-1 in single-crystal boron arsenide (BAs) has led to interest in the potential application of this semiconductor for thermal management. Although both the electron/hole high mobilities have been calculated for BAs, there is a lack of experimental investigation of its electronic properties. Here, a photoluminescence (PL) measurement of single-crystal BAs at different temperatures and pressures is reported. The measurements reveal an indirect bandgap and two donor-acceptor pair (DAP) recombination transitions. Based on first-principles calculations and time-of-flight secondary-ion mass spectrometry results, the two DAP transitions are confirmed to originate from Si and C impurities occupying shallow energy levels in the bandgap. High-pressure PL spectra show that the donor level with respect to the conduction band minimum shrinks with increasing pressure, which affects the release of free carriers from defect states. These findings suggest the possibility of strain engineering of the transport properties of BAs for application in electronic devices.
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Affiliation(s)
- Xianghai Meng
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Akash Singh
- Materials Research Centre, Indian Institute of Science, Bangalore, 560012, India
| | - Rinkle Juneja
- Materials Research Centre, Indian Institute of Science, Bangalore, 560012, India
| | - Yanyao Zhang
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Fei Tian
- Department of Physics and Texas Center for Superconductivity at the University of Houston (TcSUH), University of Houston, Houston, TX, 77204, USA
| | - Zhifeng Ren
- Department of Physics and Texas Center for Superconductivity at the University of Houston (TcSUH), University of Houston, Houston, TX, 77204, USA
| | - Abhishek K Singh
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Li Shi
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
- Texas Materials Institute, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Jung-Fu Lin
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, TX, 78712, USA
- Texas Materials Institute, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Yaguo Wang
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
- Texas Materials Institute, The University of Texas at Austin, Austin, TX, 78712, USA
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12
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Bellin C, Pawbake A, Paulatto L, Béneut K, Biscaras J, Narayana C, Polian A, Late DJ, Shukla A. Functional Monochalcogenides: Raman Evidence Linking Properties, Structure, and Metavalent Bonding. PHYSICAL REVIEW LETTERS 2020; 125:145301. [PMID: 33064510 DOI: 10.1103/physrevlett.125.145301] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 08/17/2020] [Accepted: 09/09/2020] [Indexed: 06/11/2023]
Abstract
Pressure- and temperature-dependent Raman scattering in GeSe, SnSe, and GeTe for pressures beyond 50 GPa and for temperatures ranging from 78 to 800 K allow us to identify structural and electronic phase transitions, similarities between GeSe and SnSe, and differences with GeTe. Calculations help to deduce the propensity of GeTe for defect formation and the doping that results from it, which gives rise to strong Raman damping beyond anomalous anharmonicity. These properties are related to the underlying chemical bonding and consistent with a recent classification of bonding in several chalcogenide materials that puts GeTe in a separate class of "incipient" metals.
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Affiliation(s)
- Christophe Bellin
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Université, UMR CNRS 7590, MNHN, 4 Place Jussieu, F-75005 Paris, France
| | - Amit Pawbake
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Université, UMR CNRS 7590, MNHN, 4 Place Jussieu, F-75005 Paris, France
- Institut Neel CNRS/UGA UPR2940, MCBT, 25 rue des Martyrs BP 166, 38042 Grenoble cedex 9, France
| | - Lorenzo Paulatto
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Université, UMR CNRS 7590, MNHN, 4 Place Jussieu, F-75005 Paris, France
| | - Keevin Béneut
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Université, UMR CNRS 7590, MNHN, 4 Place Jussieu, F-75005 Paris, France
| | - Johan Biscaras
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Université, UMR CNRS 7590, MNHN, 4 Place Jussieu, F-75005 Paris, France
| | - Chandrabhas Narayana
- Chemistry and Physics of Materials Unit, School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064, India
| | - Alain Polian
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Université, UMR CNRS 7590, MNHN, 4 Place Jussieu, F-75005 Paris, France
| | - Dattatray J Late
- Centre for Nanoscience and Nanotechnology Amity University Maharashtra, Mumbai- Pune Expressway, Bhatan, Post Somatne, Panvel, Mumbai, Maharashtra 410206, India
| | - Abhay Shukla
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Université, UMR CNRS 7590, MNHN, 4 Place Jussieu, F-75005 Paris, France
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13
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Jiang K, Cui A, Shao S, Feng J, Dong H, Chen B, Wang Y, Hu Z, Chu J. New Pressure Stabilization Structure in Two-Dimensional PtSe 2. J Phys Chem Lett 2020; 11:7342-7349. [PMID: 32787291 DOI: 10.1021/acs.jpclett.0c01813] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The frequency shifts and lattice dynamics to unveil the vibrational properties of platinum diselenide (PtSe2) are investigated using pressure-dependent polarized Raman scattering at room temperature up to 25 GPa. The two phonon modes Eg and A1g display similar hardening trends; both the Raman peak positions and full widths at half-maximum have distinct mutation phenomena under high pressure. Especially, the split Eg mode at 4.3 GPa confirms the change of the lattice symmetry. With the aid of the first-principles calculations, a new pressure stabilization structure C2/m of PtSe2 has been found to be in good agreement with experiments. The band structures calculations reveal that the new phase is a novel type-I Dirac semimetal. The results demonstrate that the pressure-dependent Raman spectra combined with theoretical predictions may open a new window for searching and controlling the phase structure and Dirac cones of two-dimensional materials.
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Affiliation(s)
- Kai Jiang
- Technical Center for Multifunctional Magneto-Optical Spectroscopy (Shanghai), Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), Department of Materials, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Anyang Cui
- Technical Center for Multifunctional Magneto-Optical Spectroscopy (Shanghai), Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), Department of Materials, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Sen Shao
- State Key Laboratory of Superhard Materials & International Center for Computational Method and Software, Jilin University, Changchun 130012, China
| | - Jiajia Feng
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Hongliang Dong
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Bin Chen
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Yanchao Wang
- State Key Laboratory of Superhard Materials & International Center for Computational Method and Software, Jilin University, Changchun 130012, China
| | - Zhigao Hu
- Technical Center for Multifunctional Magneto-Optical Spectroscopy (Shanghai), Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), Department of Materials, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
- Shanghai Institute of Intelligent Electronics & Systems, Fudan University, Shanghai 200433, China
| | - Junhao Chu
- Technical Center for Multifunctional Magneto-Optical Spectroscopy (Shanghai), Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), Department of Materials, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
- Shanghai Institute of Intelligent Electronics & Systems, Fudan University, Shanghai 200433, China
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14
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Roy PK, Luxa J, Sofer Z. Emerging pnictogen-based 2D semiconductors: sensing and electronic devices. NANOSCALE 2020; 12:10430-10446. [PMID: 32377656 DOI: 10.1039/d0nr02932g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Pnictogens are an intensively studied group of monoelemental two-dimensional materials. This group of elements consists of phosphorus, arsenic, antimony, and bismuth. In this group, the elements adopt two different layered structural allotropes, orthorhombic structure with true van der Waals layered interactions and rhombohedral structure, where covalent interactions between layers are also present. The orthorhombic structure is well known for phosphorus and arsenic, and the rhombohedral structure is the most thermodynamically stable allotropic modification of arsenic, antimony, and bismuth. Due to the electronic structure of pnictogen layers and their semiconducting character, these materials have huge application potential for electronic devices such as transistors and sensors including photosensitive devices as well as gas and electrochemical sensors. While photodetection and gas sensing applications are often related to lithography processed materials, chemical sensing proceeds in a liquid environment (either aqueous or non-aqueous) and can be influenced by surface oxidation of these materials. In this review, we explore the current state of pnictogen applications in sensing and electronic devices including transistors, photodetectors, gas sensors, and chemical/electrochemical sensors.
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Affiliation(s)
- Pradip Kumar Roy
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague 6, Czech Republic.
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15
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Alencar RS, Rabelo C, Miranda HLS, Vasconcelos TL, Oliveira BS, Ribeiro A, Públio BC, Ribeiro-Soares J, Filho AGS, Cançado LG, Jorio A. Probing Spatial Phonon Correlation Length in Post-Transition Metal Monochalcogenide GaS Using Tip-Enhanced Raman Spectroscopy. NANO LETTERS 2019; 19:7357-7364. [PMID: 31469281 DOI: 10.1021/acs.nanolett.9b02974] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The knowledge of the phonon coherence length is of great importance for two-dimensional-based materials since phonons can limit the lifetime of charge carriers and heat dissipation. Here we use tip-enhanced Raman spectroscopy (TERS) to measure the spatial correlation length Lc of the A1g1 and A1g2 phonons of monolayer and few-layer gallium sulfide (GaS). The differences in Lc values are responsible for different enhancements of the A1g modes, with A1g1 always enhancing more than the A1g2, independently of the number of GaS layers. For five layers, the results show an Lc of 64 and 47 nm for A1g1 and A1g2, respectively, and the coherence lengths decrease when decreasing the number of layers, indicating that scattering with the surface roughness plays an important role.
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Affiliation(s)
- R S Alencar
- Faculdade de Física , Universidade Federal do Pará , 66075-110 Belém-PA , Brazil
- Departamento de Física , Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais 30270-901 , Brazil
- Departamento de Física , Centro de Ciências, Universidade Federal do Ceará , P. O. Box 6030, Fortaleza , Ceará 60455-900 , Brazil
| | - Cassiano Rabelo
- Programa de Pós-Graduação em Engenharia Elétrica , Universidade Federal de Minas Gerais , Av. Antônio Carlos 6627 , 31270-901 Belo Horizonte , MG , Brazil
| | - Hudson L S Miranda
- Programa de Pós-Graduação em Engenharia Elétrica , Universidade Federal de Minas Gerais , Av. Antônio Carlos 6627 , 31270-901 Belo Horizonte , MG , Brazil
| | - Thiago L Vasconcelos
- Divisão de Metrologia de Materiais , Instituto Nacional de Metrologia Qualidade e Tecnologia (INMETRO) , Duque de Caxias, Rio de Janeiro 25250-020 , Brazil
| | - Bruno S Oliveira
- Divisão de Metrologia de Materiais , Instituto Nacional de Metrologia Qualidade e Tecnologia (INMETRO) , Duque de Caxias, Rio de Janeiro 25250-020 , Brazil
| | - Aroldo Ribeiro
- Departamento de Física , Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais 30270-901 , Brazil
| | - Bruno C Públio
- Departamento de Física , Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais 30270-901 , Brazil
| | - Jenaina Ribeiro-Soares
- Departamento de Física , Universidade Federal de Lavras , Lavras , Minas Gerais 37200-000 , Brazil
| | - A G Souza Filho
- Departamento de Física , Centro de Ciências, Universidade Federal do Ceará , P. O. Box 6030, Fortaleza , Ceará 60455-900 , Brazil
| | - Luiz Gustavo Cançado
- Departamento de Física , Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais 30270-901 , Brazil
| | - Ado Jorio
- Departamento de Física , Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais 30270-901 , Brazil
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