On two different kinds of resonances in one-dimensional   quantum-mechanical models
  We apply the Riccati-Pad\'{e} method and the Rayleigh-Ritz method with complex rotation to the study of the resonances of a one-dimensional well with two barriers. The model exhibits two different kinds of resonances and we calculate them by means of both approaches. While the Rayleigh-Ritz method reveals each set at a particular interval of rotation angles the Riccati Pad\'{e} method yields both of them as roots of the same Hankel determinants. 
Francisco M. Fern\'andez and Javier Garcia
quant-ph