José Concepción Torres-Guzmán
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
José Concepción Torres-Guzmán has a total of 23 co-authors. Here are the top co-authors by number of shared publications:
A. Díaz-De-Anda
3 shared publicationsAlfredo Díaz-De-Anda
Instituto de Física Benemérita Universidad Autónoma de Puebla P.O. Box J-48 72570 Puebla Puebla México
2 shared publications- Alfredo Díaz-De-Anda
Benemerita Univ Autonoma Puebla, Inst Fis, POB J-48, Puebla 72570, Mexico
2 shared publications W. Rodríguez-Cruz
2 shared publications- A. Arreola-Lucas
Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, Iztapalapa, Ciudad de México, México
1 shared publication A.M. Martínez-Argüello
1 shared publication
Latest Publications
- Open Access
- 17 February 2026
- Published by Elsevier in Wave Motion
- Vol. 144
Signatures of the second spectrum of bending modes in beams with variable cross-sections
- 17 February 2026
- Published by Elsevier in Wave Motion
- Vol. 144
Open AccessSignatures of the second spectrum of bending modes in beams with variable cross-sections
- Open Access
- 19 July 2025
- Published by MDPI AG in Nanomaterials
- Vol. 15 (14) , 1125
Optical Response Tailoring via Morphosynthesis of Ag@Au Nanoparticles
We present a simple method for customizing the optical characteristics of gold-core, silver-shell (Au@Ag) nanoparticles through controlled morphosynthesis via a seed-mediated chemical reduction approach. By systematically adjusting the concentration of cetyltrimethylammonium chloride (CTAC), we obtained precise control over both the thickness of the Ag shell and the particle shape, transitioning from spherical nanoparticles to distinctly defined nanocubes. Bright field and high-angle annular dark-field scanning transmission electron microscopy (BF-STEM and HAADF-STEM), and energy-dispersive X-ray spectroscopy (EDS) were employed to validate the structural and compositional changes. To link morphology with optical behavior, we utilized the Mie and Maxwell–Garnett theoretical models to simulate the dielectric response of the core–shell nanostructures, showing trends that align with experimental UV-visible absorption spectra. This research presents an easy and adjustable method for modifying the plasmonic properties of Ag@Au nanoparticles by varying their shape and shell, offering opportunities for advanced applications in sensing, photonics, and nanophotonics.
- 19 July 2025
- Published by MDPI AG in Nanomaterials
- Vol. 15 (14) , 1125
Open AccessOptical Response Tailoring via Morphosynthesis of Ag@Au Nanoparticles
We present a simple method for customizing the optical characteristics of gold-core, silver-shell (Au@Ag) nanoparticles through controlled morphosynthesis via a seed-mediated chemical reduction approach. By systematically adjusting the concentration of cetyltrimethylammonium chloride (CTAC), we obtained precise control over both the thickness of the Ag shell and the particle shape, transitioning from spherical nanoparticles to distinctly defined nanocubes. Bright field and high-angle annular dark-field scanning transmission electron microscopy (BF-STEM and HAADF-STEM), and energy-dispersive X-ray spectroscopy (EDS) were employed to validate the structural and compositional changes. To link morphology with optical behavior, we utilized the Mie and Maxwell–Garnett theoretical models to simulate the dielectric response of the core–shell nanostructures, showing trends that align with experimental UV-visible absorption spectra. This research presents an easy and adjustable method for modifying the plasmonic properties of Ag@Au nanoparticles by varying their shape and shell, offering opportunities for advanced applications in sensing, photonics, and nanophotonics.
- Open Access
- 7 May 2024
- Published by IOP Publishing in Journal of Physics A: Mathematical and Theoretical
- Vol. 57 (20) , 205201
Exact closed forms for the transmittance of electromagnetic waves in one-dimensional anisotropic periodic media
In this work, we obtain closed expressions for the transfer matrix and the transmittance of electromagnetic waves propagating in finite one-dimensional anisotropic periodic stratified media with an arbitrary number of cells. By invoking the Cayley–Hamilton theorem on the transfer matrix for the electromagnetic field in a periodic stratified media formed byNcells, we obtain a fourth-order recursive relation for the matrix coefficients that defines the so-called Tetranacci polynomials (TPs). In the symmetric case, corresponding to a unit-cell transfer matrix with a characteristic polynomial where the coefficients of the linear and cubic terms are equal, closed expressions for the solutions to the recursive relation, known as symmetric TPs, have recently been derived, allowing us to write the transfer matrix and transmittance in a closed form. We show as sufficient conditions that the differential propagation matrix of each layer in the binary unit cell, , has eigenvalues of the form , , with , and its off-diagonal block matrices possess the same symmetric structure in both layers. Otherwise, the recursive relations are still solvable for any matrix and provide an algorithm to compute theNth power of the transfer matrix without carrying out explicitly the matrix multiplication ofNmatrices. We obtain analytical expressions for the dispersion relation and transmittance, in closed form, for two finite periodic systems: the first one consists of two birefringent uniaxial media with their optical axis perpendicular to thez-axis, and the second consists of two isotropic media subject to an external magnetic field oriented along thez-axis and exhibiting the Faraday effect. Our formalism applies also to lossy media, magnetic anisotropy or optical activity.- 7 May 2024
- Published by IOP Publishing in Journal of Physics A: Mathematical and Theoretical
- Vol. 57 (20) , 205201
Open AccessExact closed forms for the transmittance of electromagnetic waves in one-dimensional anisotropic periodic media
In this work, we obtain closed expressions for the transfer matrix and the transmittance of electromagnetic waves propagating in finite one-dimensional anisotropic periodic stratified media with an arbitrary number of cells. By invoking the Cayley–Hamilton theorem on the transfer matrix for the electromagnetic field in a periodic stratified media formed byNcells, we obtain a fourth-order recursive relation for the matrix coefficients that defines the so-called Tetranacci polynomials (TPs). In the symmetric case, corresponding to a unit-cell transfer matrix with a characteristic polynomial where the coefficients of the linear and cubic terms are equal, closed expressions for the solutions to the recursive relation, known as symmetric TPs, have recently been derived, allowing us to write the transfer matrix and transmittance in a closed form. We show as sufficient conditions that the differential propagation matrix of each layer in the binary unit cell, , has eigenvalues of the form , , with , and its off-diagonal block matrices possess the same symmetric structure in both layers. Otherwise, the recursive relations are still solvable for any matrix and provide an algorithm to compute theNth power of the transfer matrix without carrying out explicitly the matrix multiplication ofNmatrices. We obtain analytical expressions for the dispersion relation and transmittance, in closed form, for two finite periodic systems: the first one consists of two birefringent uniaxial media with their optical axis perpendicular to thez-axis, and the second consists of two isotropic media subject to an external magnetic field oriented along thez-axis and exhibiting the Faraday effect. Our formalism applies also to lossy media, magnetic anisotropy or optical activity. - Open Access
- 11 March 2024
- Published by Elsevier in Results in Physics
- Vol. 59
Exact closed forms for the transfer matrix of free oscillations in finite periodic Timoshenko–Ehrenfest beams
- 11 March 2024
- Published by Elsevier in Results in Physics
- Vol. 59
Open AccessExact closed forms for the transfer matrix of free oscillations in finite periodic Timoshenko–Ehrenfest beams
- Open Access
Exact closed forms for the transmittance of electromagnetic waves in one-dimensional anisotropic periodic media
In this work, we obtain closed expressions for the transfer matrix and the transmittance of electromagnetic waves propagating in finite 1D anisotropic periodic stratified media with an arbitrary number of cells. By invoking the Cayley-Hamilton theorem on the transfer matrix for the electromagnetic field in a periodic stratified media formed by N cells, we obtain a fourth-degree recursive relation for the matrix coefficients that defines the so-called Tetranacci Polynomials. In the symmetric case, corresponding to a unit-cell transfer matrix with a characteristic polynomial where the coefficients of the linear and cubic terms are equal, closed expressions for the solutions to the recursive relation, known as symmetric Tetranacci Polynomials, have recently been derived, allowing us to write the transfer matrix and transmittance in a closed form. We show as sufficient conditions that the $4\times4$ differential propagation matrix of each layer in the binary unit cell, $Δ$, a) has eigenvalues of the form $\pm p_1$, $\pm p_2$, with $p_1\ne p_2$, and b) its off-diagonal $2\times2$ block matrices possess the same symmetric structure in both layers. Otherwise, the recursive relations are still solvable for any $4\times4$-matrix and provide an algorithm to compute the N-th power of the transfer matrix without carrying out explicitly the matrix multiplication of N matrices. We obtain analytical expressions for the dispersion relation and transmittance, in closed form, for two finite periodic systems: the first one consists of two birefringent uniaxial media with their optical axis perpendicular to the z-axis, and the second consists of two isotropic media subject to an external magnetic field oriented along the z-axis and exhibiting the Faraday effect. Our formalism applies also to lossy media, magnetic anisotropy or optical activity.Open AccessExact closed forms for the transmittance of electromagnetic waves in one-dimensional anisotropic periodic media
In this work, we obtain closed expressions for the transfer matrix and the transmittance of electromagnetic waves propagating in finite 1D anisotropic periodic stratified media with an arbitrary number of cells. By invoking the Cayley-Hamilton theorem on the transfer matrix for the electromagnetic field in a periodic stratified media formed by N cells, we obtain a fourth-degree recursive relation for the matrix coefficients that defines the so-called Tetranacci Polynomials. In the symmetric case, corresponding to a unit-cell transfer matrix with a characteristic polynomial where the coefficients of the linear and cubic terms are equal, closed expressions for the solutions to the recursive relation, known as symmetric Tetranacci Polynomials, have recently been derived, allowing us to write the transfer matrix and transmittance in a closed form. We show as sufficient conditions that the $4\times4$ differential propagation matrix of each layer in the binary unit cell, $Δ$, a) has eigenvalues of the form $\pm p_1$, $\pm p_2$, with $p_1\ne p_2$, and b) its off-diagonal $2\times2$ block matrices possess the same symmetric structure in both layers. Otherwise, the recursive relations are still solvable for any $4\times4$-matrix and provide an algorithm to compute the N-th power of the transfer matrix without carrying out explicitly the matrix multiplication of N matrices. We obtain analytical expressions for the dispersion relation and transmittance, in closed form, for two finite periodic systems: the first one consists of two birefringent uniaxial media with their optical axis perpendicular to the z-axis, and the second consists of two isotropic media subject to an external magnetic field oriented along the z-axis and exhibiting the Faraday effect. Our formalism applies also to lossy media, magnetic anisotropy or optical activity. - 13 December 2021
- Published by Springer Nature in The European Physical Journal Plus
- Vol. 137 (1) , 1-20
Frequency level repulsion and exchange of normal-mode shapes at avoided crossings in 1D dissimilar coupled elastic resonators
- 13 December 2021
- Published by Springer Nature in The European Physical Journal Plus
- Vol. 137 (1) , 1-20
Frequency level repulsion and exchange of normal-mode shapes at avoided crossings in 1D dissimilar coupled elastic resonators
- Open Access
- 9 September 2021
- Published by Oxford University Press (OUP) in Journal of Mechanics
- Vol. 37, 532-542
Frequency filter for elastic bending waves: Poincaré map method and experiment
In this work, the Poincaré map numerical method was successfully developed to solve the fourth-order differential equation that describes the flexural vibrations of a beam, within the Timoshenko beam theory. The Euler-Bernoulli continuity conditions were considered, which are valid for frequencies smaller than the critical frequency. As an example, this method was used to design a complex elastic structure, characterized by a flexural frequency spectrum with a broad band gap. Such structure consists of two coupled phononic crystals, which were designed with filling factor values in such a way that in their bending frequency spectra, an allowed band of the first part, overlaps with a band gap of the second one and vice versa. The resulting composed system has a much wider effective gap than its original components, between 4 and 10.5 kHz. This system works as an elastic bending wave filter. Finally, these three structured elastic systems were constructed, and characterized by the acoustic resonance spectroscopy technique. The natural flexural frequencies as well as the corresponding wave amplitudes of each structured beam were measured. The experimental measurements show excellent agreement with the numerical simulation.
- 9 September 2021
- Published by Oxford University Press (OUP) in Journal of Mechanics
- Vol. 37, 532-542
Open AccessFrequency filter for elastic bending waves: Poincaré map method and experiment
In this work, the Poincaré map numerical method was successfully developed to solve the fourth-order differential equation that describes the flexural vibrations of a beam, within the Timoshenko beam theory. The Euler-Bernoulli continuity conditions were considered, which are valid for frequencies smaller than the critical frequency. As an example, this method was used to design a complex elastic structure, characterized by a flexural frequency spectrum with a broad band gap. Such structure consists of two coupled phononic crystals, which were designed with filling factor values in such a way that in their bending frequency spectra, an allowed band of the first part, overlaps with a band gap of the second one and vice versa. The resulting composed system has a much wider effective gap than its original components, between 4 and 10.5 kHz. This system works as an elastic bending wave filter. Finally, these three structured elastic systems were constructed, and characterized by the acoustic resonance spectroscopy technique. The natural flexural frequencies as well as the corresponding wave amplitudes of each structured beam were measured. The experimental measurements show excellent agreement with the numerical simulation.
- 1 March 2021
- Published by IOP Publishing in Europhysics Letters
- Vol. 133 (6)
Wannier-Stark ladders in free oscillations of Timoshenko-Ehrenfest beams
We report on the observation of Wannier-Stark ladders in the bending vibrations of elastic beams. By introducing a gradient in the length distribution of N weakly coupled beams, the elastic equivalent of the Wannier-Stark ladder is obtained in a system governed by two coupled second-degree differential equations, instead of the common wave equation, and whose oscillations are also dispersive and, above a certain critical frequency, occur with two wavelengths. We have measured for the first time, not only the spectrum of the ladders, but the wave amplitudes in this type of system, which are not directly accessible in quantum-mechanical systems, and we have found that the wavelengths are spatially localized and in good agreement with the theoretically predicted amplitudes. Due to the combination of differential equations and the boundary conditions imposed on the system, the Wannier-Stark ladder phenomenon occurs from the third band of states onwards, unlike other classical systems.
- 1 March 2021
- Published by IOP Publishing in Europhysics Letters
- Vol. 133 (6)
Wannier-Stark ladders in free oscillations of Timoshenko-Ehrenfest beams
We report on the observation of Wannier-Stark ladders in the bending vibrations of elastic beams. By introducing a gradient in the length distribution of N weakly coupled beams, the elastic equivalent of the Wannier-Stark ladder is obtained in a system governed by two coupled second-degree differential equations, instead of the common wave equation, and whose oscillations are also dispersive and, above a certain critical frequency, occur with two wavelengths. We have measured for the first time, not only the spectrum of the ladders, but the wave amplitudes in this type of system, which are not directly accessible in quantum-mechanical systems, and we have found that the wavelengths are spatially localized and in good agreement with the theoretically predicted amplitudes. Due to the combination of differential equations and the boundary conditions imposed on the system, the Wannier-Stark ladder phenomenon occurs from the third band of states onwards, unlike other classical systems.