Large composite fermion effective mass at filling factor 5/2
Abstract
The 5/2 fractional quantum Hall effect in the second Landau level of extremely clean two-dimensional electron gases has attracted much attention due to its topological order predicted to host quasiparticles that obey non-Abelian quantum statistics and could serve as a basis for fault-tolerant quantum computations. While previous works have establish the Fermi liquid (FL) nature of its putative composite fermion (CF) normal phase, little is known regarding its thermodynamics properties and as a result its effective mass is entirely unknown. Here, we report on time-resolved specific heat measurements at filling factor 5/2, and we examine the ratio of specific heat to temperature as a function of temperature. Combining these specific heat data with existing longitudinal thermopower data measuring the entropy in the clean limit we find that, unless a phase transition/crossover gives rise to large specific heat anomaly, both datasets point towards a large effective mass in the FL phase of CFs at 5/2. We estimate the effective-to-bare mass ratio m*/me to be ranging from ~2 to 4, which is two to three times larger than previously measured values in the first Landau level.
Keywords
Cite
@article{arxiv.2312.16135,
title = {Large composite fermion effective mass at filling factor 5/2},
author = {M. Petrescu and Z. Berkson-Korenberg and Sujatha Vijayakrishnan and K. W. West and L. N. Pfeiffer and G. Gervais},
journal= {arXiv preprint arXiv:2312.16135},
year = {2023}
}