@article{TREJO201414,

title = {Theoretical approach to the phonon modes and specific heat of germanium nanowires},

author = {A. Trejo and L. L\'{o}pez-Palacios and R. V\'{a}zquez-Medina and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0921452614003706},

doi = {https://doi.org/10.1016/j.physb.2014.05.005},

issn = {0921-4526},

year  = {2014},

date = {2014-01-01},

journal = {Physica B: Condensed Matter},

volume = {453},

pages = {14-18},

abstract = {The phonon modes and specific heat of Ge nanowires were computed using a first principles density functional theory scheme with a generalized gradient approximation and finite-displacement supercell algorithms. The nanowires were modeled in three different directions: [001], [111], and [110], using the supercell technique. All surface dangling bonds were saturated with Hydrogen atoms. The results show that the specific heat of the GeNWs at room temperature increases as the nanowire diameter decreases, regardless the orientation due to the phonon confinement and surface passivation. Also the phonon confinement effects could be observed since the highest optical phonon modes in the Ge vibration interval shifted to a lower frequency compared to their bulk counterparts.},

note = {Low-Dimensional Semiconductor Structures - A part of the XXII International Material Research Congress (IMRC 2013)},

keywords = {Germanium, Nanowires, Phonons, Specific Heat},

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}

}