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Long Range Interactions in Quantum Many Body Problem in One-Dimension:Ground State

Saugata Ghosh
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Abstract

We investigate the ground state properties of a family of $N$-body systems in 1-dimension, trapped in a polynomial potential and having long range 2-body interaction in addition to the inverse square potential studied in the Calogero-Sutherland model (CSM). We show that for such a Hamiltonian, the ground state energy is similar to that of free fermions in a harmonic well with a displacement that depends on the number of particles and depth of the well. We obtain the ground state wave function and using random matrix results, study the particle density and pair correlation function (PCF). We observe that the particles are arranged in bands. Due to the presence of long range interaction, the PCF shows a departure from the CSM.

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Saugata Ghosh. 2004-01-20. Long Range Interactions in Quantum Many Body Problem in One-Dimension:Ground State. https://doi.org/10.1103/physreve.69.036118

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