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Liu C, Cyphert EL, Stephen SJ, Wang B, Morales AL, Nixon JC, Natsoulas NR, Garcia M, Blazquez Carmona P, Vill AC, Donnelly EL, Brito IL, Vashishth D, Hernandez CJ. Microbiome-induced Increases and Decreases in Bone Tissue Strength can be Initiated After Skeletal Maturity. bioRxiv 2024:2024.01.03.574074. [PMID: 38260539 PMCID: PMC10802367 DOI: 10.1101/2024.01.03.574074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Recent studies in mice have indicated that the gut microbiome can regulate bone tissue strength. However, prior work involved modifications to the gut microbiome in growing animals and it is unclear if the same changes in the microbiome, applied later in life, would change matrix strength. Here we changed the composition of the gut microbiome before and/or after skeletal maturity (16 weeks of age) using oral antibiotics (ampicillin + neomycin). Male and female mice (n=143 total, n=12-17/group/sex) were allocated into five study groups:1) Unaltered, 2) Continuous (dosing 4-24 weeks of age), 3) Delayed (dosing only 16-24 weeks of age), 4) Initial (dosing 4-16 weeks of age, suspended at 16 weeks), and 5) Reconstituted (dosing from 4-16 weeks following by fecal microbiota transplant from Unaltered donors). Animals were euthanized at 24 weeks of age. In males, bone matrix strength in the femur was 25-35% less than expected from geometry in mice from the Continuous (p= 0.001), Delayed (p= 0.005), and Initial (p=0.040) groups as compared to Unaltered. Reconstitution of the gut microbiota, however, led to a bone matrix strength similar to Unaltered animals (p=0.929). In females, microbiome-induced changes in bone matrix strength followed the same trend as males but were not significantly different, demonstrating sex-related differences in the response of bone matrix to the gut microbiota. Minor differences in chemical composition of bone matrix were observed (Raman spectroscopy). Our findings indicate that microbiome-induced impairment of bone matrix in males can be initiated and/or reversed after skeletal maturity. The portion of the femoral cortical bone formed after skeletal maturity (16 weeks) is small; however, this suggests that microbiome-induced changes in bone matrix occur without osteoblast/osteoclast turnover using an, as of yet unidentified mechanism. These findings add to evidence that the mechanical properties of bone matrix can be altered in the adult skeleton.
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Affiliation(s)
- C Liu
- Departments of Orthopaedic Surgery and Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - E L Cyphert
- Departments of Orthopaedic Surgery and Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - S J Stephen
- Shirley Ann Jackson, PhD Center for Biotechnology and Interdisciplinary Studies, Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - B Wang
- Shirley Ann Jackson, PhD Center for Biotechnology and Interdisciplinary Studies, Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - A L Morales
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - J C Nixon
- Departments of Orthopaedic Surgery and Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
- Shirley Ann Jackson, PhD Center for Biotechnology and Interdisciplinary Studies, Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
- Escuela Técnica Superior de Ingeniería, Universidad de Sevilla, Spain
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
- Department of Material Science and Engineering, Cornell University, Ithaca, NY, USA
- Reseach Division, Hospital for Special Surgery, New York, NY, USA
- Rensselaer - Icahn School of Medicine at Mount Sinai Center for Engineering and Precision Medicine, New York, NY
- Chan Zuckerberg Biohub San Francisco, CA, US
| | - N R Natsoulas
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - M Garcia
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | | | - A C Vill
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - E L Donnelly
- Department of Material Science and Engineering, Cornell University, Ithaca, NY, USA
- Reseach Division, Hospital for Special Surgery, New York, NY, USA
| | - I L Brito
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - D Vashishth
- Shirley Ann Jackson, PhD Center for Biotechnology and Interdisciplinary Studies, Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
- Rensselaer - Icahn School of Medicine at Mount Sinai Center for Engineering and Precision Medicine, New York, NY
| | - C J Hernandez
- Departments of Orthopaedic Surgery and Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
- Chan Zuckerberg Biohub San Francisco, CA, US
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Cyphert EL, Liu C, Morales AL, Nixon JC, Blackford E, Garcia M, Cevallos N, Turnbaugh PJ, Brito IL, Booth SL, Hernandez CJ. Effects of long-term high dose aspartame on body mass, bone strength, femoral geometry, and microbiota composition in a young and aged cohort of male and female mice. bioRxiv 2024:2024.01.02.573970. [PMID: 38260245 PMCID: PMC10802297 DOI: 10.1101/2024.01.02.573970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Background Recent reassessment of the safety of aspartame has prompted increased evaluation of its effect on the health of a range of tissues. The gut microbiome is altered by oral aspartame. One prior study suggested that changes in the microbiome caused by aspartame could influence the strength of bone in young skeletally developing mice. Here we ask how aspartame influences bone in mice of different age and sex. Objective The objective of this study was to determine the effect of aspartame on the bone strength and gut microbiota of young and aged mice. Methods Male and female C57Bl/6J mice were untreated or treated with a high dose of aspartame in their drinking water from 1 month of age until 4 (young cohort; n = 80) or 22 months (aged cohort; n = 52). Results In aged males, mice treated with aspartame had greater body mass, whole bone strength, and femoral geometry relative to untreated. Specifically, in aged males, aspartame led to 9% increase in body mass (p < 0.001), 22% increase in whole bone strength (p = 0.006), and 17% increase in section modulus (p < 0.001) relative to untreated mice. Aged males and females receiving aspartame had a different microbiota than untreated mice and a decreased abundance of Odoribacter. No differences in body mass, whole bone strength, or femoral geometry were associated with aspartame dosing in young males or young or aged females. Conclusions Aspartame treated aged males had greater whole bone strength and the effect appeared to be explained by greater body mass. Aspartame treatment did not alter whole bone strength in young males or young or aged females despite the aspartame having a similar effect on the microbiota of both aged males and females.
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Affiliation(s)
- Erika L. Cyphert
- Department of Orthopaedic Surgery, University of California San Francisco, 400 Parnassus Avenue, San Francisco, CA 94143
- Sibley School of Mechanical & Aerospace Engineering, Cornell University, 124 Hoy Road, Ithaca, NY 14853
| | - Chongshan Liu
- Sibley School of Mechanical & Aerospace Engineering, Cornell University, 124 Hoy Road, Ithaca, NY 14853
| | - Angie L. Morales
- Sibley School of Mechanical & Aerospace Engineering, Cornell University, 124 Hoy Road, Ithaca, NY 14853
| | - Jacob C. Nixon
- Sibley School of Mechanical & Aerospace Engineering, Cornell University, 124 Hoy Road, Ithaca, NY 14853
| | - Emily Blackford
- Sibley School of Mechanical & Aerospace Engineering, Cornell University, 124 Hoy Road, Ithaca, NY 14853
| | - Matthew Garcia
- Sibley School of Mechanical & Aerospace Engineering, Cornell University, 124 Hoy Road, Ithaca, NY 14853
| | - Nicolas Cevallos
- Department of Orthopaedic Surgery, University of California San Francisco, 400 Parnassus Avenue, San Francisco, CA 94143
| | - Peter J. Turnbaugh
- Department of Microbiology and Immunology, University of California San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143
- Chan Zuckerberg Biohub – San Francisco, San Francisco, CA 94143
| | - Ilana L. Brito
- Meinig School of Biomedical Engineering, Cornell University, 101 Weill Hall, Ithaca, NY 14853
| | - Sarah L. Booth
- Jean Mayer USDA Human Nutrition Research Center on Aging, 711 Washington Street, Tufts University, Boston, MA 02111
| | - Christopher J. Hernandez
- Department of Orthopaedic Surgery, University of California San Francisco, 400 Parnassus Avenue, San Francisco, CA 94143
- Chan Zuckerberg Biohub – San Francisco, San Francisco, CA 94143
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, 400 Parnassus Avenue, San Francisco, CA 94158
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León-González JC, Toscano-Negrette RG, Morales AL, Vinasco JA, Yücel MB, Sari H, Kasapoglu E, Sakiroglu S, Mora-Ramos ME, Restrepo RL, Duque CA. Spin-Orbit and Zeeman Effects on the Electronic Properties of Single Quantum Rings: Applied Magnetic Field and Topological Defects. Nanomaterials (Basel) 2023; 13:nano13091461. [PMID: 37177005 PMCID: PMC10180153 DOI: 10.3390/nano13091461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/05/2023] [Accepted: 04/11/2023] [Indexed: 05/15/2023]
Abstract
Within the framework of effective mass theory, we investigate the effects of spin-orbit interaction (SOI) and Zeeman splitting on the electronic properties of an electron confined in GaAs single quantum rings. Energies and envelope wavefunctions in the system are determined by solving the Schrödinger equation via the finite element method. First, we consider an inversely quadratic model potential to describe electron confining profiles in a single quantum ring. The study also analyzes the influence of applied electric and magnetic fields. Solutions for eigenstates are then used to evaluate the linear inter-state light absorption coefficient through the corresponding resonant transition energies and electric dipole matrix moment elements, assuming circular polarization for the incident radiation. Results show that both SOI effects and Zeeman splitting reduce the absorption intensity for the considered transitions compared to the case when these interactions are absent. In addition, the magnitude and position of the resonant peaks have non-monotonic behavior with external magnetic fields. Secondly, we investigate the electronic and optical properties of the electron confined in the quantum ring with a topological defect in the structure; the results show that the crossings in the energy curves as a function of the magnetic field are eliminated, and, therefore, an improvement in transition energies occurs. In addition, the dipole matrix moments present a non-oscillatory behavior compared to the case when a topological defect is not considered.
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Affiliation(s)
- José C León-González
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia
- Departamento de Física y Electrónica, Universidad de Córdoba, Carrera 6 No. 77-305, Montería 230002, Colombia
| | - Rafael G Toscano-Negrette
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia
- Departamento de Física y Electrónica, Universidad de Córdoba, Carrera 6 No. 77-305, Montería 230002, Colombia
| | - A L Morales
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia
| | - J A Vinasco
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia
| | - M B Yücel
- Department of Physics, Faculty of Science, Akdeniz University, 07058 Antalya, Turkey
| | - H Sari
- Department of Mathematical and Natural Science, Faculty of Education, Sivas Cumhuriyet University, 58140 Sivas, Turkey
| | - E Kasapoglu
- Department of Physics, Faculty of Science, Sivas Cumhuriyet University, 58140 Sivas, Turkey
| | - S Sakiroglu
- Dokuz Eylul University, Faculty of Science, Physics Department, 35390 Izmir, Turkey
| | - M E Mora-Ramos
- Centro de Investigación en Ciencias, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Cuernavaca CP 62209, Morelos, Mexico
| | | | - C A Duque
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia
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Mora-Ramos ME, Vinasco JA, Laroze D, Radu A, Restrepo RL, Heyn C, Tulupenko V, Hieu NN, Phuc HV, Ojeda JH, Morales AL, Duque CA. Electronic structure of vertically coupled quantum dot-ring heterostructures under applied electromagnetic probes. A finite-element approach. Sci Rep 2021; 11:4015. [PMID: 33597625 PMCID: PMC7889662 DOI: 10.1038/s41598-021-83583-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 02/04/2021] [Indexed: 11/21/2022] Open
Abstract
We theoretically investigate the electron and hole states in a semiconductor quantum dot-quantum ring coupled structure, inspired by the recent experimental report by Elborg and collaborators (2017). The finite element method constitutes the numerical technique used to solve the three-dimensional effective mass equation within the parabolic band approximation, including the effects of externally applied electric and magnetic fields. Initially, the features of conduction electron states in the proposed system appear discussed in detail, under different geometrical configurations and values of the intensity of the aforementioned electromagnetic probes. In the second part, the properties of an electron-hole pair confined within the very kind of structure reported in the reference above are investigated via a model that tries to reproduce as close as possible the developed profile. In accordance, we report on the energies of confined electron and hole, affected by the influence of an external electric field, revealing the possibility of field-induced separate spatial localization, which may result in an indirect exciton configuration. In relation with this fact, we present a preliminary analysis of such phenomenon via the calculation of the Coulomb integral.
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Affiliation(s)
- M E Mora-Ramos
- Centro de Investigación en Ciencias-IICBA, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209 Cuernavaca, Morelos, Mexico.
| | - J A Vinasco
- Instituto de Alta Investigación, CEDENNA, Universidad de Tarapacá, Casilla 7D, Arica, Chile
| | - D Laroze
- Instituto de Alta Investigación, CEDENNA, Universidad de Tarapacá, Casilla 7D, Arica, Chile
| | - A Radu
- Department of Physics, University Politehnica of Bucharest, 313 Splaiul Independenţei, Bucharest, 060042, Romania
| | | | - Christian Heyn
- Center for Hybrid Nanostructures (CHyN), University of Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - V Tulupenko
- Donbass State Engineering Academy, Academichna str. 62, Kramatorsk, 84313, Ukraine.,Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - Nguyen N Hieu
- Institute of Research and Development, Duy Tan University, Da Nang, 550000, Viet Nam.,Faculty of Natural Sciences, Duy Tan University, Da Nang, 550000, Viet Nam
| | - Huynh V Phuc
- Division of Theoretical Physics, Dong Thap University, Cao Lanh, 870000, Viet Nam
| | - J H Ojeda
- Grupo de Física de Materiales, Facultad de Ciencias, Universidad Pedagógica y Tecnológica de Colombia, Tunja, Boyacá, Colombia
| | - A L Morales
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - C A Duque
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
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Mora-Ramos ME, El Aouami A, Feddi E, Radu A, Restrepo RL, Vinasco JA, Morales AL, Duque CA. Donor impurity energy and optical absorption in spherical sector quantum dots. Heliyon 2020; 6:e03194. [PMID: 31989050 PMCID: PMC6970157 DOI: 10.1016/j.heliyon.2020.e03194] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 12/05/2019] [Accepted: 01/07/2020] [Indexed: 12/04/2022] Open
Abstract
The properties of the conduction band energy states of an electron interacting with a donor impurity center in spherical sector-shaped GaAs-Al0.3Ga0.7As quantum dots are theoretically investigated. The study is performed within the framework of the effective mass approximation through the numerical solution of the 3D Schrödinger equation for the envelope function via the finite element method. The modifications undergone by the spectrum due to the changes in the conical structure geometry (radius and apical angle) as well as in the position of the donor atom are discussed. With the information regarding electron states the linear optical absorption coefficient associated with transition between confined energy levels is evaluated and its features are discussed. The comparison of results obtained within the considered model with available experimental data in GaAs truncated-whisker-like quantum dots shows very good agreement. Besides, our simulation leads to identify the lowest energy photoluminescence peak as donor-related, instead of being associated to acceptor atoms, as claimed after experimental measurement (Hiruma et al. (1995) [14]). Also, a checking of our numerical approach is performed by comparing with analytical solutions to the problem of a spherical cone-shaped GaN with infinite confinement and donor impurity located at the cone apex. Coincidence is found to be remarkable.
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Affiliation(s)
- M E Mora-Ramos
- Centro de Investigación en Ciencias, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209, Cuernavaca, Morelos, Mexico.,Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - A El Aouami
- Laboratoire de Matiére Condenssée et Sciences Interdisciplinaires (LaMCScI), Group of Optoelectronic of Semiconductors and Nanomaterials, ENSET, Mohammed V University in Rabat, Morocco
| | - E Feddi
- Laboratoire de Matiére Condenssée et Sciences Interdisciplinaires (LaMCScI), Group of Optoelectronic of Semiconductors and Nanomaterials, ENSET, Mohammed V University in Rabat, Morocco
| | - A Radu
- Department of Physics, "Politehnica" University of Bucharest, 313 Splaiul Independenţei, Bucharest, RO-060042, Romania
| | | | - J A Vinasco
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - A L Morales
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - C A Duque
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
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Vinasco JA, Radu A, Kasapoglu E, Restrepo RL, Morales AL, Feddi E, Mora-Ramos ME, Duque CA. Effects of Geometry on the Electronic Properties of Semiconductor Elliptical Quantum Rings. Sci Rep 2018; 8:13299. [PMID: 30185886 PMCID: PMC6125586 DOI: 10.1038/s41598-018-31512-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 08/13/2018] [Indexed: 11/09/2022] Open
Abstract
The electronic states in GaAs-AlxGa1-xAs elliptically-shaped quantum rings are theoretically investigated through the numerical solution of the effective mass band equation via the finite element method. The results are obtained for different sizes and geometries, including the possibility of a number of hill-shaped deformations that play the role of either connected or isolated quantum dots (hills), depending on the configuration chosen. The quantum ring transversal section is assumed to exhibit three different geometrical symmetries - squared, triangular and parabolic. The behavior of the allowed confined states as functions of the cross-section shape, the ring dimensions, and the number of hills-like structures are discussed in detail. The effective energy bandgap (photoluminescence peak with electron-hole correlation) is reported as well, as a function of the Al molar fraction.
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Affiliation(s)
- J A Vinasco
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - A Radu
- Department of Physics, "Politehnica" University of Bucharest, 313 Splaiul Independenţei, Bucharest, RO, 060042, Romania
| | - E Kasapoglu
- Faculty of Science, Department of Physics, Cumhuriyet University, 58140, Sivas, Turkey
| | | | - A L Morales
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - E Feddi
- Laboratoire de Matière Condensée et Sciences Interdisciplinaires (LaMCScI) Group of Optoelectronic of Semiconductors and Nanomaterials ENSET, Mohammed V University in Rabat, Rabat, Morocco
| | - M E Mora-Ramos
- Centro de Investigación en Ciencias-IICBA, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209, Cuernavaca, Morelos, Mexico
| | - C A Duque
- Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia.
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Monsaleve-Calderón K, Gil-Corrales A, Morales AL, Restrepo RL, Mora-Ramos ME, Duque CA. Electron Raman Scattering and Raman Gain in Pyramidal Semiconductor Quantum Dots. J Nanosci Nanotechnol 2017; 17:1140-1148. [PMID: 29676880 DOI: 10.1166/jnn.2017.12657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The Raman scattering related with conduction band states in semiconductor pyramidal quantum dots is theoretically investigated. The electron Raman differential cross section and Raman gain coefficient are calculated making use of analytically determined quantum states. The energy spectrum is obtained within the effective mass approximation. The features of the Raman differential cross section are discussed in terms of their dependence on the changes of the quantum dot geometry. The variation of the Raman gain coefficient as a function of the quantum dot size and shape is also analyzed.
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Almbladh CO, Morales AL. Phonon effects on deep-level excitations in metals: beyond the linear-screening and linear-coupling models. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0305-4608/15/4/023] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Almbladh C, Morales AL, Grossmann G. Theory of Auger core-valence-valence processes in simple metals. I. Total yields and core-level lifetime widths. Phys Rev B Condens Matter 1989; 39:3489-3502. [PMID: 9948663 DOI: 10.1103/physrevb.39.3489] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Almbladh C, Morales AL. Theory of Auger core-valence-valence processes in simple metals. II. Dynamical and surface effects on Auger line shapes. Phys Rev B Condens Matter 1989; 39:3503-3516. [PMID: 9948664 DOI: 10.1103/physrevb.39.3503] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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