Very-High-Energy Collective States of Partons in Fractional Quantum Hall Liquids

The low-energy physics of fractional quantum Hall (FQH) states-a paradigm of strongly correlated topological phases of matter-to a large extent is captured by weakly interacting quasiparticles known as composite fermions. In this paper, based on numerical simulations and effective field theory, we argue that some high-energy states in the FQH spectra necessitate a different description based on parton quasiparticles. We show that Jain states at filling factor v = n=(2pn +/- 1) with integers n, p >= 2 support two kinds of collective modes: In addition to the well-known Girvin-MacDonald-Platzman (GMP) mode, they host a high-energy collective mode, which we interpret as the GMP mode of partons. We elucidate observable signatures of the parton mode in the dynamics following a geometric quench. We construct a microscopic wave function for the parton mode and demonstrate agreement between its variational energy and exact diagonalization. Using the parton construction, we derive a field theory of the Jain states and show that the previously proposed effective theories follow from our approach. Our results point to partons being real quasiparticles which, in a way reminiscent of quarks, become observable only at sufficiently high energies.

Automated summary

This paper argues that some high-energy states in the fractional quantum Hall (FQH) spectra require a different description based on parton quasiparticles, through numerical simulations and effective field theory. The study shows that Jain states at certain filling factors support two kinds of collective modes, including a high-energy collective mode interpreted as the Girvin-MacDonald-Platzman (GMP) mode of partons. Observable signatures of the parton mode in dynamics following a geometric quench are elucidated. A microscopic wave function for the parton mode is constructed and its variational energy is shown to agree with exact diagonalization. The field theory of the Jain states is derived using the parton construction, and the previously proposed effective theories are shown to be consistent with their approach. These results suggest that partons are real quasiparticles, observable only at sufficiently high energies, in a manner reminiscent of quarks.