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``Bare'' Effective Mass in Finite Sized $ν= 1/2$ Systems

A. Raghav Chari·F. D. M. Haldane
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Abstract

In this note, we discuss the effective mass of quasiparticles in finite sized $ν= 1/2$ systems in the lowest Landau level, given a natural notion we have of the Fermi surface in these finite sized systems. The effective mass is related to the difference between instantaneous density-density response functions of the ground state and excited states of the system; we do a finite size calculation for this difference for $ν= 1/2$ systems with 7, 8 and 9 fermions, and conjecture how the difference must look in the thermodynamic limit.

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A. Raghav Chari, F. D. M. Haldane. 1997-09-05. ``Bare'' Effective Mass in Finite Sized $ν= 1/2$ Systems. https://arxiv.org/abs/cond-mat/9709081

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