Dr Álvaro Miranda Durán

@article{CUEVAS2022115372,

title = {Theoretical approach to the phonon modes of GaSb nanowires},

author = {J. L. Cuevas and M. Ojeda and M. Calvino and A. Trejo and F. Salazar and A. Miranda and L. A. Perez and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S1386947722002077},

doi = {https://doi.org/10.1016/j.physe.2022.115372},

issn = {1386-9477},

year  = {2022},

date = {2022-01-01},

journal = {Physica E: Low-dimensional Systems and Nanostructures},

volume = {143},

pages = {115372},

abstract = {Gallium Antimonide nanowires (GaSbNWs) have attracted much attention due to their possible applications in mid infrared detectors, however, there are only few theoretical investigations about this material and almost none regarding its vibrational properties. In this work the phonon modes of GaSbNWs were studied using the density functional theory with the finite displacement supercell scheme. The nanowires are modeled by removing atoms outside from a circumference along the [1 1 1] direction. All surface dangling bonds were passivated with hydrogen atoms. The results show that the expected red-shift of the highest frequency modes of GaSb are hindered by low frequency H bond bending modes. Three clearly distinguishable frequency intervals were observed: One with vibrations whose main contribution come from the Ga and Sb nanowire atoms, the second interval with main contributions from H bending modes and finally a high frequency interval where the main contributions come from H stretching modes. Also, it was observed that the radial breathing mode (RBM) decreases when the nanowire diameter increases, while the contrary tendency is observed with their specific heat (the specific heat increases as the nanowire diameter increases), except in the low temperature region where the lower diameters have higher specific heat values. These results could be important for the characterization of these nanowires with IR and Raman techniques.},

keywords = {DFT, Gallium Antimonide, Nanowires, Phonons},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/qua.25713,

title = {Quantum confinement effects on the harmful-gas-sensing properties of silicon nanowires},

author = {Francisco Santiago and \'{A}lvaro Miranda and Alejandro Trejo and Fernando Salazar and Eliel Carvajal and Miguel Cruz-Irisson and Luis A. P\'{e}rez},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/qua.25713},

doi = {https://doi.org/10.1002/qua.25713},

year  = {2018},

date = {2018-01-01},

journal = {International Journal of Quantum Chemistry},

volume = {118},

number = {20},

pages = {e25713},

abstract = {Abstract In this work, the effects of the adsorption of different toxic gas molecules CO, NO, NO2, and SO2 on the electronic structure of hydrogen-passivated, [111]-oriented, silicon nanowires (H-SiNWs), are studied through density functional theory. To analyze the effects of quantum confinement, three nanowire diameters are considered. The results show that the adsorption energies are almost independent of the nanowire diameter with NO2 being the most strongly adsorbed molecule (∼3.44 eV). The electronic structure of small-diameter H-SiNWs is modified due to the creation of isolated defect-like states on molecule adsorption. However, these discrete levels are eventually hybridized with the former nanowire states as the nanowire diameter increases and quantum confinement effects become less evident. Hence, there is a range of small nanowire diameters with distinctive band gaps and adsorption energies for each molecule species.},

keywords = {Density Functional Theory, Nanowires, Sensors, silicon, toxic gases},

pubstate = {published},

tppubtype = {article}

}

@article{TREJO201292,

title = {Phonon optical modes and electronic properties in diamond nanowires},

author = {A. Trejo and A. Miranda and L. Ni\~{n}o Rivera and A. D\'{i}az-M\'{e}ndez and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S016793171100476X},

doi = {https://doi.org/10.1016/j.mee.2011.04.052},

issn = {0167-9317},

year  = {2012},

date = {2012-01-01},

journal = {Microelectronic Engineering},

volume = {90},

pages = {92-95},

abstract = {A local bond-polarization model based on the displacement\textendashdisplacement Green’s function and the Born potential are applied to study the confined optical phonons and Raman scattering of diamond nanowires (DNWs). Also, the electronic band structure of DNWs are investigated by means of a semi-empirical tight-binding approach and compared with density functional theory within local density approximation. The supercell technique is applied to model DNWs along [001] direction preserving the crystalline diamond atomic structure. The results of both phonons and electrons show a clear quantum confinement signature. Moreover, the highest energy Raman peak shows a shift towards low frequencies respect to the bulk crystalline diamond, in agreement with experimental data.},

note = {Micro\&Nano 2010},

keywords = {Diamond, Nanowires, Phonons, Raman scattering, Tight-binding},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/qua.22753,

title = {Hydrogen surface passivation of Si and Ge nanowires: A semiempirical approach},

author = {A. Miranda and F. A. Serrano and R. V\'{a}zquez-Medina and M. Cruz-Irisson},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/qua.22753},

doi = {https://doi.org/10.1002/qua.22753},

year  = {2010},

date = {2010-01-01},

urldate = {2010-01-01},

journal = {International Journal of Quantum Chemistry},

volume = {110},

number = {13},

pages = {2448-2454},

abstract = {Abstract A semiempirical nearest-neighbor tight-binding approach, that reproduces the indirect band gaps of elemental semiconductors, has been applied to study the electronic and optical properties of Si and Ge nanowires (NWs). The calculations show that Si-NWs keep the indirect bandgap whereas Ge-NWs changes into the direct bandgap when the wire cross section becomes smaller. Also, the band gap enhancement of Si-NWs showing to quantum confinement effects is generally larger than that of similar-sized Ge-NWs, confirming the larger quantum confinement effects in Si than in Ge when they are confined in two dimensions. Finally, the dependence of the imaginary part of the dielectric function on the quantum confinement within two different schemes: intra-atomic and interatomic optical matrix elements are applied. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem 110:2448\textendash2454, 2010},

keywords = {Germanium, Nanowires, optical properties, silicon, Tight-binding},

pubstate = {published},

tppubtype = {article}

}

@article{MIRANDA2009796,

title = {Quantum confinement effects on electronic properties of hydrogenated 3C\textendashSiC nanowires},

author = {A. Miranda and J. L. Cuevas and A. E. Ramos and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0026269208005375},

doi = {https://doi.org/10.1016/j.mejo.2008.11.034},

issn = {1879-2391},

year  = {2009},

date = {2009-01-01},

urldate = {2009-01-01},

journal = {Microelectronics Journal},

volume = {40},

number = {4},

pages = {796-798},

abstract = {In this work, the effect of the morphology on the electronic band structure and density of states of hydrogenated silicon carbide nanowires is studied by using a semiempirical sp3s* tight-binding (TB) approach applied to the supercell model, where the Si- and C-dangling bonds are passivated by hydrogen atoms. The TB results are compared with those of ab-initio density functional theory within the local density approximation, showing that this method gives systematically larger energy gaps than the TB one. As expected, hydrogen saturation induces a broadening of the band gap energy due to quantum confinement effect.},

note = {European Nano Systems (ENS 2007) International Conference on Superlattices, Nanostructures and Nanodevices (ICSNN 2008)},

keywords = {Density Functional Theory, Nanowires, Silicon carbide, Tight-binding},

pubstate = {published},

tppubtype = {article}

}