arXiv subjects

O. Rosas-Ortiz

Publications and source records attributed to O. Rosas-Ortiz.

10 recordsLinked to original sources

arXiv2023

Bessel-Gauss beams of arbitrary integer order: propagation profile, coherence properties and quality factor

We present a novel approach to generate Bessel-Gauss modes of arbitrary integer order and well-defined optical angular momentum in a gradient index medium of transverse parabolic profile. The propagation and coherence properties, as well as the quality factor, are studied using algebraic techniques that are widely used in quantum mechanics. It is found that imposing the well-defined optical angular momentum condition, the Lie group $SU(1,1)$ comes to light as a characteristic symmetry of the Bessel-Gauss beams.

physics.optics↗

arXiv2020

Nonclassical States for Non-Hermitian Hamiltonians with the Oscillator Spectrum

We show that the standard techniques that are utilized to study the classical like properties of the pure states for Hermitian systems can be adjusted to investigate the classicality of pure states for non-Hermitian systems. The method is applied to the states of complex-valued potentials that are generated by Darboux transformations and can model both non-PT-symmetric and PT-symmetric oscillators exhibiting real spectra.

quant-ph↗

arXiv2009

A Primer on Resonances in Quantum Mechanics

After a pedagogical introduction to the concept of resonance in classical and quantum mechanics, some interesting applications are discussed. The subject includes resonances occurring as one of the effects of radiative reaction, the resonances involved in the refraction of electromagnetic waves by a medium with a complex refractive index, and quantum decaying systems described in terms of resonant states of the energy. Some useful mathematical approaches like the Fourier transform, the complex scaling method and the Darboux transformation are also reviewed.

quant-ph↗

arXiv2009

Optical potentials using resonance states in Supersymmetric Quantum Mechanics

Complex potentials are constructed as Darboux-deformations of short range, radial nonsingular potentials. They behave as optical devices which both refracts and absorbs light waves. The deformation preserves the initial spectrum of energies and it is implemented by means of a Gamow-Siegert function (resonance state). As straightforward example, the method is applied to the radial square well. Analytical derivations of the involved resonances show that they are `quantized' while the corresponding wave-functions are shown to behave as bounded states under the broken of parity symmetry of the related one-dimensional problem.

math-ph↗

arXiv2001

Physical sectors of the confluent hypergeometric functions space

A relaxed factorization is used to obtain many of the properties obeyed by the confluent hypergeometric functions. Their implications on the analytical solutions of some interesting physical problems are also studied. It is quite remarkable that, although these properties appear frequently in solving the Schroedinger equation, it has been not clear the role they play in describing the physical systems. The main objective of this communication is precisely to throw some light on the subject.

quant-ph↗

arXiv2000

The finite difference algorithm for higher order supersymmetry

The higher order supersymmetric partners of the Schroedinger's Hamiltonians can be explicitly constructed by iterating a simple finite difference equation corresponding to the Baecklund transformation. The method can completely replace the Crum determinants. Its limiting, differential case offers some new operational advantages.

quant-ph↗

arXiv1999

Refined Factorizations of Solvable Potentials

A generalization of the factorization technique is shown to be a powerful algebraic tool to discover further properties of a class of integrable systems in Quantum Mechanics. The method is applied in the study of radial oscillator, Morse and Coulomb potentials to obtain a wide set of raising and lowering operators, and to show clearly the connection that link these systems.

quant-ph↗

arXiv1999

The supersymmetric modified Poschl-Teller and delta-well potentials

New supersymmetric partners of the modified Poschl-Teller and the Dirac's delta well potentials are constructed in closed form. The resulting one-parametric potentials are shown to be interrelated by a limiting process. The range of values of the parameters for which these potentials are free of singularities is exactly determined. The construction of higher order supersymmetric partner potentials is also investigated.

quant-ph↗

arXiv1999

Evolution loops and spin-1/2 systems

The derivation of a new family of magnetic fields inducing exactly solvable spin evolutions is presented. The conditions for which these fields generate the evolution loops (dynamical processes for which any spin state evolves cyclically) are studied. Their natural connection with geometric phases and the corresponding calculation is also elaborated.

quant-ph↗

arXiv1999

Backlund-type superposition and free particle n-susy partners

The higher order susy partners of Schroedinger Hamiltonians can be explicitly constructed by iterating a nonlinear difference algorithm coinciding with the Backlund superposition principle used in soliton theory. As an example, it is applied in the construction of new higher order susy partners of the free particle potential, which can be used as a handy tool in soliton theory.

quant-ph↗