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Related papers: Neutral Fermions at $\nu=1/2$

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It is demonstrated that all observed fractions at moderate Landau level fillings for the quantum Hall effect can be obtained without recourse to the phenomenological concept of composite fermions. The possibility to have the special…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 S. V. Iordanski

Fermions with one and two Dirac nodes are coupled to in-plane phonons to study a spontaneous transition into the Hall insulating phase. At sufficiently strong electron-phonon interaction a gap appears in the spectrum of fermions, signaling…

Strongly Correlated Electrons · Physics 2018-12-12 Andreas Sinner , Klaus Ziegler

In wide GaAs quantum wells where two electric subbands are occupied we apply a parallel magnetic field or increase the electron density to cause a crossing of the two $N=0$ Landau levels of these subbands and with opposite spins. Near the…

Mesoscale and Nanoscale Physics · Physics 2015-11-04 Yang Liu , S. Hasdemir , J. Shabani , M. Shayegan , L. N. Pfeiffer , K. W. West , K. W. Baldwin

The $\nu = 2/3$ filling is the simplest paradigmatic example of a fractional quantum Hall state, which contains counter-propagating edge modes. These modes can be either in the unequilibrated regime or equilibrated to different extents, on…

Mesoscale and Nanoscale Physics · Physics 2024-12-25 Sourav Manna , Ankur Das , Yuval Gefen , Moshe Goldstein

We propose an effective field theory (EFT) of fractional quantum Hall systems near the filling fraction $\nu=5/2$ that flows to pertinent IR candidate phases, including non-abelian Pfaffian, anti-Pfaffian, and particle-hole Pfaffian states…

Strongly Correlated Electrons · Physics 2020-11-17 Po-Shen Hsin , Ying-Hsuan Lin , Natalie M. Paquette , Juven Wang

Electron fractionalization is intimately related to topology. In one-dimensional systems, fractionally charged states exist at domain walls between degenerate vacua. In two-dimensional systems, fractionalization exists in quantum Hall…

Mesoscale and Nanoscale Physics · Physics 2008-11-26 Chang-Yu Hou , Claudio Chamon , Christopher Mudry

The natures of the ground state in a $\nu_{\rm T}=1$ bilayer quantum Hall system at a variety of layer spacing are investigated. At small layer separations the system exhibits spontaneous interlayer phase coherence. It is claimed that the…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Kentaro Nomura , Daijiro Yoshioka

Despite the fact that composite fermions may be regarded as electrically neutral objects at Landua-level filling factor $\nu=1/2$, carrying only an electric dipole moment, we argue that the long-wavelength compressibility of the system is…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 B. I. Halperin , Ady Stern

Using exact Bethe ansatz solution, we rigorously study excitation spectra of the spin-1/2 Fermi gas (called Yang-Gaudin model) with an attractive interaction. Elementary excitations of this model involve particle-hole excitations, hole…

Quantum Gases · Physics 2023-05-16 Jia-Feng Pan , Jia-Jia Luo , Xi-Wen Guan

We investigate the relationship of the spontaneously inter-layer coherent ``111''state of quantum Hall bilayers at total filling factor \nu=1 to ``mutual'' composite fermions, in which vortices in one layer are bound to electrons in the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Y. Veillette , L. Balents , Matthew P. A. Fisher

We report observations of collective gap excitations of the fractional quantum Hall (FQH) states at filling factors \nu=p/(2p+1) (p=integer), for 1/3 <= \nu <= 2/3, by inelastic light scattering. The collective gap energies at \nu= 1/3, 2/5…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Moonsoo Kang , A. Pinczuk , B. S. Dennis , M. A. Eriksson , L. N. Pfeiffer , K. W. West

Originally proposed by Read [1] and Jain [2], the so-called "composite-fermion" is a phenomenological attachment of two infinitely thin local flux quanta seen as nonlocal vortices to two-dimensional (2D) electrons embedded in a strong…

Mesoscale and Nanoscale Physics · Physics 2014-04-24 Gilbert Reinisch , Vidar Gudmundsson , Andrei Manolescu

The fractional quantum Hall effect, where plateaus in the Hall resistance at values of coexist with zeros in the longitudinal resistance, results from electron correlations in two dimensions under a strong magnetic field. Current flows…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 M. Dolev , M. Heiblum , V. Umansky , Ady Stern , D. Mahalu

Single-layer and Bilayer of graphene are new classes of two-dimensional electron systems with unconventional band structures and valley degrees of freedom. The ground states and excitations in the integer and fractional quantum Hall regimes…

Strongly Correlated Electrons · Physics 2015-05-13 Naokazu Shibata , Kentaro Nomura

In this report we summarize a recent progress in exploration of correlated two-dimensional electron states in partially filled high Landau levels. At a mean-field Hartree-Fock level they can be described as charge-density waves, either…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Michael M. Fogler

We study the critical spin-polarization energy ($\alpha_{\rm C}$) above which fractional quantum Hall states in two-dimensional electron systems confined to symmetric GaAs quantum wells become fully spin-polarized. We find a significant…

Mesoscale and Nanoscale Physics · Physics 2014-09-23 Yang Liu , S. Hasdemir , A. Wójs , J. K. Jain , L. N. Pfeiffer , K. W. West , K. W. Baldwin , M. Shayegan

It is demonstrated that all observed fractions at moderate Landau level fillings in the quantum Hall effect can be obtained without recourse to the phenomenological concept of composite fermions. The possibility to have the special…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. V. Iordanski

We study the quantum critical point between the fermionic $\nu=8$ quantum Hall state and the bosonic $\nu=2$ quantum Hall state of Cooper pairs. Our study is motivated by the composite fermion construction for the daughter states of…

Mesoscale and Nanoscale Physics · Physics 2025-08-26 Evgenii Zheltonozhskii , Ady Stern , Netanel H. Lindner

Numerical results for the energy spectra of $N$ electrons on a spherical surface are used as input data to determine the quasiparticle energies and the pairwise ``Fermi liquid'' interactions of composite Fermion (CF) excitations in…

Condensed Matter · Physics 2009-10-28 P. Sitko , S. N. Yi , K. S. Yi , J. J. Quinn

We develop a general theory of Fermi polarons at nonzero temperature, including particle-hole excitations of the Fermi sea shake-up to arbitrarily high orders. The exact set of equations of the spectral function is derived by using both…

Quantum Gases · Physics 2024-08-21 Hui Hu , Jia Wang , Xia-Ji Liu