Yu. A. Pusep

Universidade de São Paulo

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

J. C. Galzerani

Universidade Federal de São Carlos

A. G. Milekhin

Institute of Semiconductor Physics

C. A. de Souza

Universidade de São Paulo

Adenilson J. Chiquito

Universidade Federal de São Carlos

D. Lubyshev

IQE (United States)

P. Basmaji

Innovatech (Brazil)

H. Arakaki

Universidade de São Paulo

A. I. Toropov

Institute of Semiconductor Physics

Ray LaPierre

McMaster University

S.W. da Silva

Universidade de Brasília

Cooperative Institutions

Universidade de São Paulo

Universidade Federal de São Carlos

Institute of Semiconductor Physics

Russian Academy of Sciences

Siberian Branch of the Russian Academy of Sciences

Centre National de la Recherche Scientifique

Novosibirsk State University

Universidade Estadual de Campinas (UNICAMP)

Max Planck Society

Institut National des Sciences Appliquées de Toulouse

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Parallel conductivity of random GaAs/AlGaAs superlattices in regime of controlled vertical disorder

Journal of Applied Physics (2002)

Yu. A. Pusep Adenilson J. Chiquito S. Mergulhão A. I. Toropov

The transport properties of intentionally disordered short-period doped GaAs/AlGaAs superlattices were explored. We found that a redistribution of the electron density in a random potential significantly influences the electron properties of the disordered superlattices resulting in a suppression of the vertical disorder and in the increase of the in-plane mobility of the layers with increasing disorder.

Redistribution

Charge-carrier density

Electron Mobility

10.1063/1.1506002

Cite

Citations (18)

INHOMOGENEITY OF ELECTRON LIQUID AND EFFECTS OF INTERLAYER COUPLING IN GaAs/AlGaAs SUPERLATTICES IN THE REGIME OF THE QUANTUM HALL EFFECT

International Journal of Modern Physics B (2007)

Yu. A. Pusep Francisco Eduardo Gontijo Guimarães H. Arakaki C. A. de Souza Adenilson J. Chiquito

Formation of the electron state with the integer filling factor was studied by magneto-capacitance and magneto-photoluminescence measurements in weakly coupled GaAs/AlGaAs multilayers where quasi-two dimensional electrons revealed the integer Quantum Hall Effect. The disorder modulated compressibility of the quantized Hall phase with the filling factor ν=2 was determined. The incompressible fraction of this phase was shown to rapidly disappear with the increasing temperature. The quantized Hall phase of the weakly coupled multilayers was shown to emit the asymmetrical photoluminescence lines. We demonstrated that the observed asymmetry is caused by a partial population of the extended electron states formed in the quantized Hall conductor phase due to the disorder induced interlayer tunneling.

Filling factor

Wigner crystal

10.1142/s0217979207042914

Cite

Citations (0)

Raman study of Fano-like electron-phonon coupling in δ-doping GaAs superlattices

Physical review. B, Condensed matter (1996)

Yu. A. Pusep M. T. O. Silva J. C. Galzerani S.W. da Silva L. M. R. Scolfaro

The interaction between electron excitations and LO phonons was studied by Raman scattering in \ensuremath{\delta}-doping GaAs superlattices. The off-resonant spectra, to which the deformation potential contributes, reveal the coupling of the LO phonons with the superlattice plasmon; however, those measured close to the ${\mathit{E}}_{0}$+${\mathrm{\ensuremath{\Delta}}}_{0}$ resonance of GaAs present both the Fano-like coupling of the LO phonons with the quasicontinuum single-particle electron excitations and the coupling of the LO phonons with macroscopic depolarization fields of the intersubband electron excitations. It was shown that the Fr\"ohlich interaction is responsible for the Fano-type electron--LO-phonon coupling. Due to the self-consistent origin of the electron-energy spectrum in \ensuremath{\delta}-doping superlattices, the resonance of the Fano interference was found to be strongly dependent on the electron density as well as on the excitation energy. \textcopyright{} 1996 The American Physical Society.

Fano resonance

Fano plane

10.1103/physrevb.54.13927

Cite

Citations (8)

Magnetic field driven interminiband charge transfer in InGaAs/InP superlattices

Journal of Physics Condensed Matter (2015)

Yu. A. Pusep Bruno G. Tavares M. A. T. Patricio L. Fernandes dos Santos Ray LaPierre

The characteristic energies, occupancies and polarizations of the minibands formed by the Γ-Γ and Γ-Xz interlayer electon tunnelings in the InGaAs/InP superlattices are studied in the regime of the integer quantum Hall effect by polarization resolved photoluminescence. Accordingly, the magnetic field induced shrinkage of the interminiband gap, predicted by the theory, and as a consequence, the redistribution of charge over the superlattice minibands and the depolarization of the quantum Hall electron states are observed at odd filling factors. The response of the electrons residing in the InGaAs/InP superlattice minibands to the magnetic field is found very similar to the corresponding response of the electrons confined in the symmetric and anti-symmetric two-dimensional minibands of GaAs/AlGaAs double quantum wells. The presented results are evidence of the formation of the correlated states in multi-component electron systems formed in semiconductor multiple layers at odd filling factors.

10.1088/0953-8984/27/24/245601

Cite

Citations (3)

Raman measurement of vertical conductivity and localization effects in strongly coupled semiconductor periodical structures

Journal of Applied Physics (2000)

Yu. A. Pusep M. T. O. Silva J. C. Galzerani S. C. P. Rodrigues L. M. R. Scolfaro

Raman scattering was applied to a study of collective plasmon–LO phonon excitations polarized normal to the layers in strongly coupled GaAs/AlAs and δ-doped GaAs superlattices. Thus, the corresponding (vertical) motion of electrons and their localization were studied and compared in both types of superlattices. The localization of the collective excitations caused by the localization of the electrons at the top of the miniband was found in the GaAs/AlAs superlattices. Much stronger localization effects were observed in the δ-doped structures than in the GaAs/AlAs superlattices. Our results reveal evidence of the formation of a miniband structure in the δ-doped structures even in the case of complete localization of electrons inside one period.

Electron localization function

Weak localization

Anderson Localization

10.1063/1.372097

Cite

Citations (3)

Interference effects in nonplanar wires with a two-dimensional electron gas

Physics of low-Dimensional structures (1998)

P. Basmaji G. M. Gusev Newton La Scala Pedro Pablo González‐Borrero D. Lubyshev

Source

Cite

Citations (0)

Study of the segregation process in GaAs/AlAs superlattices using Raman spectroscopy

Journal of Raman Spectroscopy (2001)

G. Zanelato Yu. A. Pusep J. C. Galzerani D. Lubyshev Pedro Pablo González‐Borrero

Abstract A Raman scattering study of cation segregation in GaAs/AlAs ultrathin‐layer superlattices grown with different temperatures and As pressures is reported. The optical confined modes of the samples were measured. The kinetic segregation model was modified in order to allow the calculation of the compositional profiles of the samples. After utilizing the Raman wavenumbers as references to adjust the calculated values by the next‐nearest‐neighbor linear chain model, it was possible to determine the parameters characterizing the segregation. It is shown that an increase in the pressure of As results in a more abrupt compositional profile, equivalent to the decrease in the growth temperature. Copyright © 2001 John Wiley & Sons, Ltd.

Wavenumber

10.1002/jrs.774

Cite

Citations (0)

Magnetotransport in a wide parabolic well superimposed with a superlattice

Journal of Applied Physics (2011)

Yu. A. Pusep G. M. Gusev A. K. Bakarov A. I. Toropov J. C. Portal

The electron properties of artificially disordered superlattices embedded in a wide AlGaAs parabolic well were investigated in a strong magnetic field. We demonstrated that in the extreme quantum limit the interlayer disorder results in formation of a new correlated phase. A nearly uniform electron distribution over the superlattice wells was found in a weak magnetic field. However, a nonuniform phase with partially localized electrons, representing well-developed fractional quantum Hall effect features, was observed in high magnetic field (at the filling factor ν < 1). A distinct magnetic field–induced transition separates these two phases.

10.1063/1.3576134

Cite

Citations (0)

Resonance structure in PbSnTe reflection spectra due to charge-carrier localization

ZhETF Pisma Redaktsiiu (1987)

Yu. A. Pusep M. P. Sinyukov

Reflection

Charge carrier

Source

Cite

Citations (0)

IR Fourier spectroscopy of double-quantum-well GaAs/AlAs heterostructures