Sudip Kumar Haldar

Level-spacing statistics and spectral correlations in diffuse van der Waals clusters

We present a statistical analysis of eigenenergies and discuss several measures of spectral fluctuations and spectral correlations for the van der Waals clusters of different sizes. We show that the clusters become more and more complex with increase in cluster size. We study nearest-neighbour level spacing distribution

Correlated many-body calculation to study characteristics of Shannon information entropy for ultracold trapped interacting bosons

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DYNAMICAL FEATURES OF SHANNON INFORMATION ENTROPY OF BOSONIC CLOUD IN A TIGHT TRAP

, the level number variance

Resonance States and Quantum Tunneling of Bose Einstein condensates in a 3D shallow trap

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Condensate fraction and critical temperature of interacting Bose gas in anharmonic trap

, and the Dyson-Mehta

Spectral fluctuation and 1/fα noise in the energy level statistics of interacting trapped bosons.

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Energy-level statistics of interacting trapped bosons

statistics for various cluster sizes. For large clusters we find that although the Bohigas-Giannoni-Schmit (BGS) conjecture seems to be valid, it does not exhibit true signatures of quantum chaos. However contrasting conjecture of Berry and Tabor is observed with smaller cluster size. For small number of bosons, we observe the existence of large number of quasi-degenerate states in low-lying excitation which exhibits the Shnirelman peak in

Supersymmetric isospectral formalism for the calculation of near-zero energy states: application to the very weakly bound 4 He trimer excited state

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Macroscopic quantum many-body tunneling of attractive Bose-Einstein condensate in anharmonic trap

distribution. We also find a narrow region of intermediate spectrum which can be described by semi-Poisson statistics whereas the higher levels are regular and exhibit Poisson statistics. These observations are further supported by the analysis of the distribution of the ratio of consecutive level spacings

Quantum many-body tunneling of attractive Bose-Einstein condensate through double asymmetric barrier

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