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Spin Structure of Many-Body Systems with Two-Body Random Interactions

Lev Kaplan·Thomas Papenbrock·Calvin W. Johnson
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Abstract

We investigate the spin structure of many-fermion systems with a spin-conserving two-body random interaction. We find a strong dominance of spin-0 ground states and considerable correlations between energies and wave functions of low-lying states with different spin, but no indication of pairing. The spectral densities exhibit spin-dependent shapes and widths, and depend on the relative strengths of the spin-0 and spin-1 couplings in the two-body random matrix. The spin structure of low-lying states can largely be explained analytically.

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Lev Kaplan, Thomas Papenbrock, Calvin W. Johnson. 2000-07-06. Spin Structure of Many-Body Systems with Two-Body Random Interactions. https://doi.org/10.1103/physrevc.63.014307

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