4 papers
Isochronous bifurcations in a two-parameter twist map
Michele Mugnaine, Bruno B. Leal, Alfredo M. Ozorio de Almeida +2
Isochronous islands in phase space emerge in twist Hamiltonian systems as a response to multiple resonant perturbations. According to the Poincaré-Birkhoff theorem, the number of i…
Phase space geometry of general quantum energy transitions
Alfredo M. Ozorio de Almeida
The mixed density operator for coarsegrained eigenlevels of a static Hamiltonian is represented in phase space by the spectral Wigner function, which has its peak on the correspond…
Semiclassical approximation of the Wigner function for the canonical ensemble
Marcos Gil de Oliveira, Alfredo Miguel Ozorio de Almeida
The Weyl-Wigner representation of quantum mechanics allows one to map the density operator in a function in phase space - the Wigner function - which acts like a probability distri…
Isochronous island bifurcations driven by resonant magnetic perturbations in Tokamaks
B. B. Leal, I. L. Caldas, M. C. de Sousa +2
Recent evidences show that heteroclinic bifurcations in magnetic islands may be caused by the amplitude variation of resonant magnetic perturbations in tokamaks. To investigate the…