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

S. K. Haldar, B. Chakrabarti, N. D. Chavda, T. K. Das, S. Canuto, and V. K. B. Kota
Phys. Rev. A 89, 043607 – Published 9 April 2014

Abstract

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-neighbor level-spacing distribution P(s), the level number variance Σ2(L), and the Dyson-Mehta Δ3 statistics for various cluster sizes. For large clusters we find that although the Bohigas-Giannoni-Schmit 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 a small number of bosons, we observe the existence of a large number of quasidegenerate states in low-lying excitation which exhibits the Shnirelman peak in P(s) 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 P(r) which is independent of unfolding procedure and thereby provides a tool for more transparent comparison with experimental findings than P(s). Thus our detail numerical study clearly shows that the van der Waals clusters become more correlated with the increase in cluster size.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
6 More
  • Received 11 November 2013

DOI:https://doi.org/10.1103/PhysRevA.89.043607

©2014 American Physical Society

Authors & Affiliations

S. K. Haldar1, B. Chakrabarti2,*, N. D. Chavda3, T. K. Das4, S. Canuto5, and V. K. B. Kota6

  • 1Department of Physics, Lady Brabourne College, P-1/2 Suhrawardi Avenue, Kolkata-700017, India
  • 2Department of Physics, Kalyani University, Kalyani, Nadia 741235, West Bengal, India
  • 3Applied Physics Department, Faculty of Technology and Engineering, Maharaja Sayajirao University of Baroda, Vadodara 390 001, India
  • 4Department of Physics, Calcutta University, 92 A. P. C. Road, Kolkata-700009, India
  • 5Instituto de Fisica, Universidade of São Paulo, CP 66318, 05315-970, São Paulo, Brazil
  • 6Physical Research Laboratory, Navarangpura, Ahmedabad 380009, India

  • *Present address: Department of Physics, Presidency University, 86/1 College Street, Kolkata 700073, India.

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 89, Iss. 4 — April 2014

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review A

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×