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Related papers: Composite Fermions with a Warped Fermi Contour

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We report on an observation of a fractional quantum Hall effect in an ultra-high quality two-dimensional hole gas hosted in a strained Ge quantum well. The Hall resistance reveals precisely quantized plateaus and vanishing longitudinal…

Mesoscale and Nanoscale Physics · Physics 2015-11-18 Q. Shi , M. A. Zudov , C. Morrison , M. Myronov

We report magnetotransport measurements of fractional quantum Hall states in an AlAs quantum well around Landau level filling factor nu = 3/2, demonstrating that the quasiparticles are composite Fermions (CFs) with a valley degree of…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 N. C. Bishop , M. Padmanabhan , K. Vakili , Y. P. Shkolnikov , E. P. De Poortere , M. Shayegan

We achieve an explicit construction of the lowest Landau level (LLL) projected wave functions for composite fermions in the periodic (torus) geometry. To this end, we first demonstrate how the vortex attachment of the composite fermion (CF)…

Strongly Correlated Electrons · Physics 2017-11-08 Songyang Pu , Ying-Hai Wu , J. K. Jain

One of the most spectacular experimental findings in the fractional quantum Hall effect is evidence for an emergent Fermi surface when the electron density is nearly half the density of magnetic flux quanta ($\nu = 1/2$). The seminal work…

Strongly Correlated Electrons · Physics 2016-04-14 Scott D. Geraedts , Michael P. Zaletel , Roger S. K. Mong , Max A. Metlitski , Ashvin Vishwanath , Olexei I. Motrunich

We study the interplay of particle-hole symmetry and fermion-vortex duality in multicomponent half-filled Landau levels, such as quantum Hall gallium arsenide bilayers and graphene. For the $\nu{=}1/2{+}1/2$ bilayer, we show that…

Strongly Correlated Electrons · Physics 2017-03-01 Inti Sodemann , Itamar Kimchi , Chong Wang , T. Senthil

We analyze the linear response of a half filled Landau level to long wavelength and low frequency driving forces, using Fermi liquid theory for composite fermions. This response is determined by the composite fermions quasi--particle…

Condensed Matter · Physics 2009-10-28 Ady Stern , Bertrand I. Halperin

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

The Halperin-Lee-Read Fermi sea of composite fermions (CFs) at half-filled lowest Landau level is the realization of a fascinating non-Fermi liquid metallic phase. Remarkably, experiments have found that as the width of the quantum well is…

Strongly Correlated Electrons · Physics 2024-02-02 Anirban Sharma , Ajit C. Balram , J. K. Jain

An inaccuracy of composite fermion model is identified for Landau level fillings out of 1/p, p odd. The corrected version of hierarchy for fractional quantum Hall effect is proposed by mapping onto integer effect within the cyclotron braid…

Mesoscale and Nanoscale Physics · Physics 2011-04-19 J. Jacak , L. Jacak

Motivated by a recent experiment of Willett et al. [Phys. Rev. Lett. 78, 4478 (1997)], we employ semiclassical composite-fermion theory to study the effect of a periodic density modulation on a quantum Hall system near Landau level filling…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 Felix von Oppen , Ady Stern , Bertrand I. Halperin

We present the first experimental study of the carrier density dependence of the composite fermion conductivity $\sigma^{CF}_{xx}$ at Landau level filling factors $\nu= {1/2}$ and $\nu= {3/2}$ in high-quality front-gated…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 C. -T. Liang , M. Y. Simmons , D. A. Ritchie , M. Pepper

We construct explicit lowest-Landau-level wave functions for the composite-fermion Fermi sea and its low energy excitations following a recently developed approach [Pu, Wu and Jain, Phys. Rev. B 96, 195302 (2018)] and demonstrate them to be…

Strongly Correlated Electrons · Physics 2018-10-02 Songyang Pu , Mikael Fremling , J. K. Jain

We discuss the possibility of the quantum Hall effect at half-filled Landau level in terms of the pairing of the composite fermions. In the absence of Coulomb energy, we show that the ground state of the system is described by the {\it…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Takao Morinari

The half-filled Landau level is widely believed to be described by the Halperin-Lee-Read theory of the composite Fermi liquid (CFL). In this paper, we develop a theory for the particle-hole conjugate of the CFL, the Anti-CFL, which we argue…

Strongly Correlated Electrons · Physics 2015-10-28 Maissam Barkeshli , Michael Mulligan , Matthew P. A. Fisher

The concept of composite fermions, and the related Fermion-Chern-Simons theory, have been powerful tools for understanding quantum Hall systems with a partially full lowest Landau level. We shall review some of the successes of the…

Condensed Matter · Physics 2015-06-24 Bertrand I. Halperin

While the integer quantum Hall effect of composite fermions manifests as the prominent fractional quantum Hall effect (FQHE) of electrons, the FQHE of composite fermions produces further, more delicate states, arising from a weak residual…

Strongly Correlated Electrons · Physics 2015-01-14 Ajit C. Balram , Csaba Tőke , A. Wójs , J. K. Jain

While an ordinary Fermi sea is perturbatively robust to interactions, the paradigmatic composite-fermion (CF) Fermi sea arises as a non-perturbative consequence of emergent gauge fields in a system where there was no Fermi sea to begin…

Strongly Correlated Electrons · Physics 2015-11-02 Ajit C. Balram , Csaba Tőke , J. K. Jain

By developing an algorithm for evaluating the basis states for the composite fermions with negative effective magnetic field, we perform the composite-fermion-diagonalization study for the fully spin-polarized fractional quantum Hall states…

Mesoscale and Nanoscale Physics · Physics 2015-12-14 Sutirtha Mukherjee , Sudhansu S. Mandal

NMR measurements of the electron spin polarization have been performed on a 2D electron system at and around half-filled lowest Landau level. Comparing the magnetic field and the temperature dependence of the spin polarization to models of…

Mesoscale and Nanoscale Physics · Physics 2016-08-16 N. Freytag , M. Horvatić , C. Berthier , M. Shayegan , L. P. Lévy

Measurements of the reflectivity of a 2-D electron gas are used to deduce the polarization of the Composite Fermion hole system formed for Landau level occupancies in the regime 1<\nu<2. The measurements are consistent with the formation of…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 R. Chughtai , V. Zhitomirsky , R. J. Nicholas , M. Henini