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Related papers: Composite Fermions with Spin at $\nu =1/2$

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Phonon excitations of fractional quantum Hall states at filling factors nu = 1/3, 2/5, 4/7, 3/5, 4/3, and 5/3 are experimentally shown to be based on Landau level transitions of Composite Fermions. At filling factor nu = 2/3, however, a…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 F. Schulze-Wischeler , F. Hohls , U. Zeitler , D. Reuter , A. D. Wieck , R. J. Haug

We report the results of two fundamental transport measurements at a Landau level filling factor $\nu$ of 1/2. The well known ballistic electron transport phenomena of quenching of the Hall effect in a mesoscopic cross-junction and negative…

Condensed Matter · Physics 2009-10-28 J. E. F. Frost , C. -T. Liang , D. R. Mace , M. Y. Simmons , D. A. Ritchie , M. Pepper

We present a theory of composite fermion edge states and their transport properties in the fractional and integer quantum Hall regimes. We show that the effective electro-chemical potentials of composite fermions at the edges of a Hall bar…

Condensed Matter · Physics 2009-10-28 George Kirczenow , Brad L. Johnson

Composite fermions provide a simple and unified picture to understand a vast amount of phenomenology in the quantum Hall regime. However it has remained challenging to formulate this concept properly within a single Landau level. Recently a…

Strongly Correlated Electrons · Physics 2022-01-25 Ken K. W. Ma , Kun Yang

The multitude of excitations of the fractional quantum Hall state are very accurately understood, microscopically, as excitations of composite fermions across their Landau-like $\Lambda$ levels. In particular, the dispersion of the…

Strongly Correlated Electrons · Physics 2017-06-26 Ajit C. Balram , Songyang Pu

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

Exact diagonalization studies have revealed that the energy spectrum of interacting electrons in the lowest Landau level splits, non-perturbatively, into bands, which is responsible for the fascinating phenomenology of this system. The…

Strongly Correlated Electrons · Physics 2013-12-02 Ajit C. Balram , Arkadiusz Wójs , Jainendra K. Jain

Strong electron correlations lie at the origin of transformative phenomena such as colossal magneto-resistance and high-temperature superconductivity. Already near room temperature, doped copper oxide materials display remarkable features…

Mechanism of the particle-flux separation in the Chern-Simons gauge theory coupled with nonrelativistic fermions is studied in a nonperturbative method. This problem is very important for the composite fermion approach to the fractional…

Condensed Matter · Physics 2009-10-28 I. Ichinose , T. Matsui

For quantum Hall systems, in the limit of large magnetic field (or equivalently small electron band mass $m_b$), the static response of electrons to a spatially varying magnetic field is largely determined by kinetic energy considerations.…

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

Composite fermions (CFs), exotic quasi-particles formed by pairing an electron and an even number of magnetic flux quanta emerge at high magnetic fields in an interacting electron system, and can explain phenomena such as the fractional…

Mesoscale and Nanoscale Physics · Physics 2022-07-19 K. A. Villegas Rosales , P. T. Madathil , Y. J. Chung , L. N. Pfeiffer , K. W. West , K. W. Baldwin , M. Shayegan

We study the applicability of composite fermion theory to electrons in two-dimensional parabolically-confined quantum dots in a strong perpendicular magnetic field in the limit of low Zeeman energy. The non-interacting composite fermion…

Condensed Matter · Physics 2009-10-28 R. K. Kamilla , J. K. Jain

Composite fermions (CFs) of the fractional quantum Hall effect are described as spherical products of electron and vortex spinors, built from underlying L=1/2 ladder operators aligned so that the spinor angular momenta Le and Lv are…

Strongly Correlated Electrons · Physics 2018-09-26 W. C. Haxton , Daniel J. Haxton , Byungmin Kang

The $\nu=2/5$ state is spin-unpolarized at weak magnetic field and fully polarized at strong field. At intermediate field, a plateau of half the maximal polarization is observed. We study this phenomenon in the frame of composite fermion…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Shi-Jie Yang , Yue Yu , Bang-Fen Zhu

The correlations in the ground state of interacting electrons in a two-dimensional quantum dot in a high magnetic field are known to undergo a qualitative change from liquid-like to crystal-like as the total angular momentum becomes large.…

Mesoscale and Nanoscale Physics · Physics 2018-09-25 Gun Sang Jeon , Chia-Chen Chang , Jainendra K. Jain

The activation gap $\Delta$ of the fractional quantum Hall states at constant fillings $\nu =2/3$ and 2/5 has been measured as a function of the perpendicular magnetic field $B$. A linear dependence of $\Delta$ on $B$ is observed while…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 F. Schulze-Wischeler , E. Mariani , F. Hohls , R. J. Haug

The fractional quantum Hall effect (FQHE) at the filling factor with an even denominator, 5/2, occurs despite the expectation, due to the electron statistics, that the denominator must be an odd number. It is believed that the Cooper…

Strongly Correlated Electrons · Physics 2024-09-12 N. Nešković , I. Vasić , M. V. Milovanović

The High Landau level filling fractions 5/2, 7/3 and 8/3 are interpreted by using the angular momentum model. It is found that for the odd number of flux quanta, the quasiparticles called the ``composite fermions'' are fermions but for even…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Keshav N. Shrivastava

The Hubbard model is used to study an electronic system at half filling. Starting from a functional integral representation the spin-up Grassmann field is integrated out. It is shown that the resulting spinless fermion theory has an…

Strongly Correlated Electrons · Physics 2007-05-23 Klaus Ziegler

We propose a fermion Chern-Simons field theory describing two- dimensional electrons in the lowest Landau level. This theory is constructed with a complete set of states, and the lowest Landau level constraint is enforced through a…

Condensed Matter · Physics 2009-10-28 Lizeng Zhang