arXiv subjects

Juan Alberto Canché-Martín

Publications and source records attributed to Juan Alberto Canché-Martín.

2 recordsLinked to original sources

arXiv2026

Conductance of silicon nanotube junctions in high magnetic fields

We investigate coherent quantum transport through silicon nanotube (SiNT) junctions in high magnetic fields up to 60 T using a tight-binding model combined with the non-equilibrium Green's function formalism, and magnetic field included via Peierls substitution. We consider junctions of metallic nanotubes (6,0)+(6,0) and semiconducting ones (9,9)+(9,9), and examine the effects of the overlap length, inter-tube distance, magnetic-field direction, and field strength on the electronic transmission. In contrast to carbon nanotube junctions, the SiNT systems exhibit irregular transmission oscillations and do not show the emergence of highly conductive gateway states. The transmission is substantially more sensitive to a magnetic field perpendicular to the nanotube axis than to a parallel field, while increasing the field strength progressively modifies the transmission spectrum. Increasing the overlap length results in more frequent transmission oscillations, whereas increasing the inter-tube distance modifies their positions and amplitudes without changing their overall character. Generally, similar trends are observed for both types of junctions, involving metallic and semiconducting nanotubes. However, in the junction of semiconducting nanotubes, one observes peculiar additional field-dependent in-gap transmission features. These results demonstrate that the magnetic-field response of SiNT junctions is strongly governed by their geometry and differs qualitatively from that of pristine carbon nanotube junctions.

cond-mat.mes-hall↗

arXiv2026

Library of carbon nanotube junctions: data-driven insights into structure-magnetotransport relationships

Electronic transport in carbon nanotube (CNT) assemblies is controlled by a heterogeneous population of CNT--CNT junctions, yet most microscopic studies consider only a few representative systems. Here, we construct a library of 146 single-walled carbon nanotube (SWCNT)--SWCNT junctions spanning broad structural and electronic diversity and analyse their magnetotransport using an automated workflow combining molecular dynamics, tight-binding theory, Peierls magnetic coupling, and non-equilibrium Green's functions.The resulting transport data are subsequently analysed using machine-learning methods. Two complementary transport descriptors reveal distinct structure--transport hierarchies. The averaged first transmission-step value is governed primarily by the mean chiral angle of the two nanotubes forming a junction, whereas the energy gap of the junction depends predominantly on the metallic or semiconducting character of the constituent CNTs. Temperature generally suppresses the averaged transmission while reducing the extracted gap, whereas a perpendicular magnetic field affects transmission much more strongly than the gap. Signatures of interference-driven transport remain visible even at $300~\mathrm{K}$. Notably, semiconducting--semiconducting junctions retain the largest gaps but, once shifted into their conducting regime, can exhibit transmission comparable to or exceeding that of metallic junctions. These results establish statistically robust junction-level trends that can inform future network-scale models of CNT assemblies.

cond-mat.mes-hall↗