Articles written in Pramana – Journal of Physics
Volume 65 Issue 1 July 2005 pp 61-74
We adopt the potential harmonics expansion method for an
Volume 69 Issue 3 September 2007 pp 329-336 Research Articles
We present and examine an approximate but
Volume 70 Issue 1 January 2008 pp 41-50 Research Articles
We present the spectral properties of supersymmetric shape invariant potentials (SIPs). Although the folded spectrum is completely random, unfolded spectrum shows that energy levels are highly correlated and absolutely rigid. All the SIPs exhibit harmonic oscillator-type spectral statistics in the unfolded spectrum. We conjecture that this is the reflection of shape invariant symmetry.
Volume 73 Issue 2 August 2009 pp 405-416
We propose a novel mathematical approach for the calculation of resonances in weakly bound systems. For any potential, families of strictly isospectral potentials (with very different shape) having desirable and adjustable features can be generated. For systems having no bound ground state, an isospectral potential with a bound state in the continuum is possible. The quasi-bound state in the original shallow potential will be effectively trapped in the deep well of the isospectral family, facilitating more accurate calculation of resonance energy. Application to 6He, 6Li and 6Be yield excellent results. Another application is the calculation of Efimov states in weakly bound three-body system. We present the result of 4He trimer, where the first excited state is claimed to be an Efimov state.