Composite fermions and the half-filled state

Journal Article · Mon Dec 01 04:00:00 EST 1997 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.56.14941· OSTI ID:554360

Marinescu, D C ^[1]; Quinn, J J ^[2]; Sitko, P ^[2]; Yi, K S ^[3]

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1. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)
2. Department of Physics, University of Tennessee, Knoxville, Tennessee 37906 (United States)
3. Department of Physics, Pusan National University, Pusan 609-735 (Korea)

Under appropriate conditions electron-hole symmetry should apply to a partially filled Landau level of a two-dimensional electron gas. This suggests that the application of Jain{close_quote}s composite fermion (CF) picture to either electrons or holes should lead to equivalent results. Surprisingly, for a system of N{sub e} electrons on a Haldane sphere, this is not true for three values of the Landau level degeneracy 2S+1. When N{sub e}{minus}1{le}S{le}N{sub e}, the sum of the electron filling factor {nu} and the hole filling factor {mu}, as determined from Jain{close_quote}s picture, is smaller than unity. Because of this, use of the relation {nu}=1{minus}{mu} can lead to {open_quotes}twin{close_quotes} or {open_quotes}alias{close_quotes} states having different values of {nu} for the same N{sub e} and 2S+1. One example is the {open_quotes}half-filled{close_quotes} state. It is determined by requiring the effective (mean-field) flux 2S{sup {asterisk}} {open_quotes}seen{close_quotes} by one CF to vanish. Different results are obtained when S{sub e}{sup {asterisk}}=S{sub e}{minus}(N{sub e}{minus}1) and S{sub h}{sup {asterisk}}=S{minus}(N{sub h}{minus}1) are set equal to zero. The same problem arises in the CF hierarchy picture when the number of quasielectrons n{sub QE} is related to the effective flux 2S{sup {asterisk}} by 2(n{sub QE}{minus}1){le}2S{sup {asterisk}}{le}2n{sub QE}. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 554360
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 23 Vol. 56; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ELECTRON GAS
FERMIONS
HALL EFFECT
MAGNETIC FIELDS
TWO-DIMENSIONAL CALCULATIONS