Comments on ``Coexistence of Composite Bosons and Composite Fermions in Quantum Hall Bilayers", Simon et al, cond-mat/0301203

TL;DR

This paper critically examines Simon et al's claims about composite fermions and bosons in quantum Hall bilayers, arguing that their proposed transitions and assumptions are inconsistent with experimental data and physical constraints.

Contribution

The authors refute the possibility of CF to CB transition in GaAs and challenge the assumptions about quasiparticle conservation and formation energy, providing a more accurate interpretation of experimental results.

Findings

CF to CB transition is not feasible in GaAs

Computed CF mass exceeds experimental values

Quasiparticle number conservation is not necessary

Abstract

Simon et al suggest that composite fermions (CF) must be replaced by composite bosons (CB) and "111" state is a boson state. However, we find that such a transition in real GaAs is not possible and CF state cannot become a boson. Simon et al suggest that the total number of CF and CB is conserved. However, we find that the number of quasiparticles need not be conserved. Similarly, Simon et al suggest that CFs are formed but we find that this formation does not conserve energy so that CFs will not be formed. Simon et al compute using products of fermion and boson wave functions. We find that the mass of the CF is much too larger than experimental mass. We find that these computed results are not in agreement with the data.