Jaime Ferreira
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Research Interests
Jaime Ferreira has a total of 20 co-authors. Here are the top co-authors by number of shared publications:
- Carsten Enderlein
Campus de Duque de Caxias, Universidade Federal do Rio de Janeiro, Estrada de Xerém 27, 25245-390 RJ, Brazil
3 shared publications - Marcello Barbosa Silva Neto
Universidade Federal do Rio de Janeiro
3 shared publications - Elisa Baggio Saitovitch
Centro Brasileiro de Pesquisas Fisicas
2 shared publications Adalberto Fazzio
Ilum School of Science
1 shared publication- Bruno Focassio
LNNano
1 shared publication - Carsten Enderlein
Universidade Federal do Rio de Janeiro
1 shared publication
Latest Publications
- Open Access
- 12 September 2024
- Published by American Physical Society (APS) in Physical Review Research
- Vol. 6 (3) , 033289
Magnetic control of Weyl nodes and wave packets in three-dimensional warped semimetals
We investigate the topological phase transitions driven by band warping, , and a transverse magnetic field, , for three-dimensional Weyl semimetals. First, we use the Chern number as a mathematical tool to derive the topological phase diagram. Next, we associate each of the topological sectors to a given angular momentum state of a rotating wave packet. Then we show how the position of the Weyl nodes can be manipulated by a transverse external magnetic field that ultimately quenches the wave packet rotation, first partially and then completely, thus resulting in a sequence of field-induced topological phase transitions. Finally, we calculate the current-induced magnetization and the anomalous Hall conductivity of a prototypical warped Weyl material. Both observables reflect the topological transitions associated with the wave packet rotation and can help to identify the elusive 3D quantum anomalous Hall effect in three-dimensional, warped Weyl materials.- 12 September 2024
- Published by American Physical Society (APS) in Physical Review Research
- Vol. 6 (3) , 033289
Open AccessMagnetic control of Weyl nodes and wave packets in three-dimensional warped semimetals
We investigate the topological phase transitions driven by band warping, , and a transverse magnetic field, , for three-dimensional Weyl semimetals. First, we use the Chern number as a mathematical tool to derive the topological phase diagram. Next, we associate each of the topological sectors to a given angular momentum state of a rotating wave packet. Then we show how the position of the Weyl nodes can be manipulated by a transverse external magnetic field that ultimately quenches the wave packet rotation, first partially and then completely, thus resulting in a sequence of field-induced topological phase transitions. Finally, we calculate the current-induced magnetization and the anomalous Hall conductivity of a prototypical warped Weyl material. Both observables reflect the topological transitions associated with the wave packet rotation and can help to identify the elusive 3D quantum anomalous Hall effect in three-dimensional, warped Weyl materials. - Open Access
- 22 April 2024
- Published by Springer Nature in Research Square
Emergent inductance and capacitance in elemental tellurium
The miniaturisation of electronic building blocks is of uttermost importance. Efficient nanoscopic inductors and capacitors could pave the way to better energy economics and therewith more powerful processors. Topological materials which exhibit emergent electromagnetism are promising candidates for such future technologies. Due to its helical crystal structure and strong spin-orbit interaction, tellurium exhibits an experimentally verified internal inductance. By formulating the constitutive equations which describe electromagnetism in tellurium, we show how capacitive and inductive properties naturally emerge in the material. We demonstrate on the basis of AC-impedance measurements that elemental tellurium exhibits an unusually high virtual capacitance and inductance, far exceeding previously studied materials. The highest capacitance we detect in our samples is 130 mF and in one of our samples we measure an extremely impressive virtual inductance of 1.5 H. For low current densities a single piece of tellurium mimics the reactance of an RLC-circuit.
- 22 April 2024
- Published by Springer Nature in Research Square
Open AccessEmergent inductance and capacitance in elemental tellurium
The miniaturisation of electronic building blocks is of uttermost importance. Efficient nanoscopic inductors and capacitors could pave the way to better energy economics and therewith more powerful processors. Topological materials which exhibit emergent electromagnetism are promising candidates for such future technologies. Due to its helical crystal structure and strong spin-orbit interaction, tellurium exhibits an experimentally verified internal inductance. By formulating the constitutive equations which describe electromagnetism in tellurium, we show how capacitive and inductive properties naturally emerge in the material. We demonstrate on the basis of AC-impedance measurements that elemental tellurium exhibits an unusually high virtual capacitance and inductance, far exceeding previously studied materials. The highest capacitance we detect in our samples is 130 mF and in one of our samples we measure an extremely impressive virtual inductance of 1.5 H. For low current densities a single piece of tellurium mimics the reactance of an RLC-circuit.
- 24 January 2023
- Published by American Physical Society (APS) in Physical Review Materials
- Vol. 7 (1) , 014204
Hedgehog orbital texture in -type tellurium and the antisymmetric nonreciprocal Hall responseTellurium is a gyrotropic, -type Weyl semiconductor with remarkable electronic, optical, and transport properties. It has been argued that some of these properties might stem from Weyl nodes at crossing points in the band structure and their nontrivial topological textures. However, Weyl nodes in time-reversal invariant semiconductors are split up in energy, rather than in momentum, and located deep below (far above) the top (bottom) of the valence (conduction) band, challenging such an interpretation. Here, instead, we use a four-band Hamiltonian for -type tellurium to show how the k-dependent spin-orbit interaction mixes up the top two (Weyl node free) and bottom two (Weyl-node-containing) valence bands, generating a 3D hedgehog orbital magnetic texture at the uppermost valence band, already accessible to transport at the lowest doping. Hedgehog textures are important signatures of Weyl fermion physics, in general, and in the context of condensed matter physics arise form the carriers' wave packet rotation being locked to their propagation wave vector. For spatially dispersive media, such an induced hedgehog texture/carrier rotation stabilizes two nonreciprocal and antisymmetric components to the Hall transport within different weak-localization (antilocalization) relaxation regimes: the anomalous and planar Hall effects, usually forbidden by time-reversal symmetry. Our AC magnetotransport measurements on Sn-doped tellurium confirm the theoretical predictions and our paper demonstrates how Weyl signatures generally appear in transport on enantiomorphic materials with natural optical activity.- 24 January 2023
- Published by American Physical Society (APS) in Physical Review Materials
- Vol. 7 (1) , 014204
Hedgehog orbital texture in -type tellurium and the antisymmetric nonreciprocal Hall responseTellurium is a gyrotropic, -type Weyl semiconductor with remarkable electronic, optical, and transport properties. It has been argued that some of these properties might stem from Weyl nodes at crossing points in the band structure and their nontrivial topological textures. However, Weyl nodes in time-reversal invariant semiconductors are split up in energy, rather than in momentum, and located deep below (far above) the top (bottom) of the valence (conduction) band, challenging such an interpretation. Here, instead, we use a four-band Hamiltonian for -type tellurium to show how the k-dependent spin-orbit interaction mixes up the top two (Weyl node free) and bottom two (Weyl-node-containing) valence bands, generating a 3D hedgehog orbital magnetic texture at the uppermost valence band, already accessible to transport at the lowest doping. Hedgehog textures are important signatures of Weyl fermion physics, in general, and in the context of condensed matter physics arise form the carriers' wave packet rotation being locked to their propagation wave vector. For spatially dispersive media, such an induced hedgehog texture/carrier rotation stabilizes two nonreciprocal and antisymmetric components to the Hall transport within different weak-localization (antilocalization) relaxation regimes: the anomalous and planar Hall effects, usually forbidden by time-reversal symmetry. Our AC magnetotransport measurements on Sn-doped tellurium confirm the theoretical predictions and our paper demonstrates how Weyl signatures generally appear in transport on enantiomorphic materials with natural optical activity.- Open Access
- 4 January 2021
- Published by Springer Nature in Communications Materials
- Vol. 2 (1) , 1-10
Pressure-induced Anderson-Mott transition in elemental tellurium
Elemental tellurium is a small band-gap semiconductor, which is always p-doped due to the natural occurrence of vacancies. Its chiral non-centrosymmetric structure, characterized by helical chains arranged in a triangular lattice, and the presence of a spin-polarized Fermi surface, render tellurium a promising candidate for future applications. Here, we use a theoretical framework, appropriate for describing the corrections to conductivity from quantum interference effects, to show that a high-quality tellurium single crystal undergoes a quantum phase transition at low temperatures from an Anderson insulator to a correlated disordered metal at around 17 kbar. Such insulator-to-metal transition manifests itself in all measured physical quantities and their critical exponents are consistent with a scenario in which a pressure-induced Lifshitz transition shifts the Fermi level below the mobility edge, paving the way for a genuine Anderson-Mott transition. We conclude that previously puzzling quantum oscillation and transport measurements might be explained by a possible Anderson-Mott ground state and the observed phase transition.
- 4 January 2021
- Published by Springer Nature in Communications Materials
- Vol. 2 (1) , 1-10
Open AccessPressure-induced Anderson-Mott transition in elemental tellurium
Elemental tellurium is a small band-gap semiconductor, which is always p-doped due to the natural occurrence of vacancies. Its chiral non-centrosymmetric structure, characterized by helical chains arranged in a triangular lattice, and the presence of a spin-polarized Fermi surface, render tellurium a promising candidate for future applications. Here, we use a theoretical framework, appropriate for describing the corrections to conductivity from quantum interference effects, to show that a high-quality tellurium single crystal undergoes a quantum phase transition at low temperatures from an Anderson insulator to a correlated disordered metal at around 17 kbar. Such insulator-to-metal transition manifests itself in all measured physical quantities and their critical exponents are consistent with a scenario in which a pressure-induced Lifshitz transition shifts the Fermi level below the mobility edge, paving the way for a genuine Anderson-Mott transition. We conclude that previously puzzling quantum oscillation and transport measurements might be explained by a possible Anderson-Mott ground state and the observed phase transition.