2001/09/19 by R. L. Willett, K. W. West, L. N. Pfeiffer
Engineering · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Composite fermion #Condensed matter physics #Electron #Fermi surface #Filling factor #Heterojunction #Materials science #Physics #Quantum Hall effect #Quantum and electron transport phenomena #Quantum mechanics #Quasiparticle #Topological Materials and Phenomena #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevlett.88.066801
11 pages, 4 figures
arxiv created 2001/09/19 · openalex publication_date 2002/01/23 · openalex created_date 2016/06/24 · arxiv updated 2016/08/31 · openalex updated_date 2026/08/05
Using small wavelength surface acoustic waves (SAW) on ultrahigh mobility heterostructures, Fermi surface properties are detected at 5/2 filling factor at temperatures higher than those at which the quantum Hall state forms. An enhanced conductivity is observed at 5/2 by employing sub-0.5-microm SAW, indicating a quasiparticle mean-free path substantially smaller than that in the lowest Landau level. These findings are consistent with the presence of a filled Fermi sea of composite fermions, which may pair at lower temperatures to form the 5/2 ground state.