ANYONIC SUPERCONDUCTIVITY WITH FERROMAGNETIC GROUND STATE

We study a system of non-relativistic two-dimensional spin-1/2 fermions minimally coupled to Chern-Simons and Maxwell gauge fields, at zero temperature. A self-consistent mean field approach leads to a ferromagnetic ground state which nevertheless is also superconducting. We calculate the spin and current correlation functions and show that there is a Meissner effect for weak external magnetic fields, characterised by two penetration lengths. The dispersion relations for the two longitudinal excitations are given. Further, the system supports spin waves which are massless in the absence of electromagnetic fields.

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A family of finite-temperature electronic phase transitions in graphene multilayers

Science ◽

10.1126/science.aar6855 ◽

2018 ◽

Vol 362 (6412) ◽

pp. 324-328 ◽

Cited By ~ 12

Author(s):

Youngwoo Nam ◽

Dong-Keun Ki ◽

David Soler-Delgado ◽

Alberto F. Morpurgo

Keyword(s):

Ground State ◽

Finite Temperature ◽

Mean Field ◽

Microscopic Theory ◽

Broken Symmetry ◽

Field Approach ◽

Electronic Phase ◽

Self Consistent ◽

Systematic Evolution ◽

Second Order Phase Transition

Suspended Bernal-stacked graphene multilayers up to an unexpectedly large thickness exhibit a broken-symmetry ground state whose origin remains to be understood. We show that a finite-temperature second-order phase transition occurs in multilayers whose critical temperature (Tc) increases from 12 kelvins (K) in bilayers to 100 K in heptalayers. A comparison of the data with a phenomenological model inspired by a mean-field approach suggests that the transition is associated with the appearance of a self-consistent valley- and spin-dependent staggered potential that changes sign from one layer to the next, appearing atTcand increasing upon cooling. The systematic evolution with thickness of several measured quantities imposes constraints on any microscopic theory aiming to analyze the nature of electronic correlations in this system.

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A Study of Finite Size Effects and Periodic Boundary Conditions to Simulations of a Novel Theoretical Self‐Consistent Mean‐Field Approach

Macromolecular Theory and Simulations ◽

10.1002/mats.201900023 ◽

2019 ◽

Vol 28 (5) ◽

pp. 1900023

Author(s):

Guanda Yang ◽

Fritjof Nilsson ◽

Dirk W. Schubert

Keyword(s):

Boundary Conditions ◽

Size Effects ◽

Periodic Boundary ◽

Mean Field ◽

Finite Size ◽

Periodic Boundary Conditions ◽

Finite Size Effects ◽

Field Approach ◽

Self Consistent

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BOSONIC CHERN-SIMONS FIELD THEORY OF ANYON SUPERCONDUCTIVITY

Modern Physics Letters A ◽

10.1142/s0217732392004109 ◽

1992 ◽

Vol 07 (28) ◽

pp. 2627-2636

Author(s):

NATHAN WEISS

Keyword(s):

Field Theory ◽

Particle Density ◽

Equations Of Motion ◽

Mean Field ◽

Meissner Effect ◽

Quantum Corrections ◽

Simple Explanation ◽

Field Solution ◽

The Mean ◽

Chern Simons

We study the quantum field theory of non-relativistic bosons coupled to a Chern-Simons gauge field at nonzero particle density. This field theory is relevant to the study of anyon superconductors in which the anyons are described as bosons with a statistical interaction. We show that it is possible to find a mean field solution to the equations of motion for this system which has some of the features of Bose condensation. The mean field solution consists of a lattice of vortices each carrying a single quantum of statistical magnetic flux. We speculate on the effects of the quantum corrections to this mean field solution. We argue that the mean field solution is only stable under quantum corrections if the Chern-Simons coefficient N=2πθ/g2 is an integer. Consequences for anyon superconductivity are presented. A simple explanation for the Meissner effect in this system is discussed.

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Self-consistent mean-field approach for the ideal anyon gas

Physical Review B ◽

10.1103/physrevb.42.7894 ◽

1990 ◽

Vol 42 (13) ◽

pp. 7894-7897 ◽

Cited By ~ 14

Author(s):

Lizeng Zhang ◽

Michael Ma ◽

Fu Chun Zhang

Keyword(s):

Mean Field ◽

Field Approach ◽

Self Consistent ◽

The Ideal

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Unconventional phase transitions in strongly anisotropic 2D (pseudo)spin systems

EPJ Web of Conferences ◽

10.1051/epjconf/201818508006 ◽

2018 ◽

Vol 185 ◽

pp. 08006

Author(s):

Vitaly Konev ◽

Evgeny Vasinovich ◽

Vasily Ulitko ◽

Yury Panov ◽

Alexander Moskvin

Keyword(s):

Magnetic Field ◽

Monte Carlo ◽

Phase Transitions ◽

Ground State ◽

Quantum Monte Carlo ◽

Mean Field ◽

Spin Systems ◽

Field Approach ◽

Generalized Mean

We have applied a generalized mean-field approach and quantum Monte-Carlo technique for the model 2D S = 1 (pseudo)spin system to find the ground state phase with its evolution under application of the (pseudo)magnetic field. The comparison of the two methods allows us to clearly demonstrate the role of quantum effects. Special attention is given to the role played by an effective single-ion anisotropy ("on-site correlation").

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HALL-MEISSNER EFFECT IN CHARGED ANYON FLUID AT T → 0

International Journal of Modern Physics B ◽

10.1142/s0217979295001415 ◽

1995 ◽

Vol 09 (27) ◽

pp. 3585-3606 ◽

Cited By ~ 3

Author(s):

E. J. FERRER ◽

V. DE LA INCERA

Keyword(s):

Electric Field ◽

Transverse Electric ◽

Meissner Effect ◽

Superconducting Phase ◽

Effective Theory ◽

Zero Temperature ◽

London Penetration Depth ◽

Magnetic Screening ◽

Statistical Limit ◽

Self Consistent

The superconducting behavior of the charged anyon fluid at finite density (µ ≠ 0) and in the zero temperature statistical limit (T → 0) is investigated in a self-consistent way. It is found that total magnetic screening appears only in the presence of a transverse electric field. This electric field is interpreted as a way to simulate, in the linear effective theory, the Hall potential associated with the vortex structure of the charged anyon system. The London penetration depth of the superconducting phase is found to be dependent on the filling factor.

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Diffusion and coupled fluxes in concentrated alloys under irradiation: a self-consistent mean-field approach

Comptes Rendus Physique ◽

10.1016/j.crhy.2007.09.001 ◽

2008 ◽

Vol 9 (3-4) ◽

pp. 362-369 ◽

Cited By ~ 8

Author(s):

Maylise Nastar

Keyword(s):

Mean Field ◽

Field Approach ◽

Self Consistent

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Mean-field Theory of the Meissner Effect in Bulk Revisited

10.20944/preprints202008.0653.v2 ◽

2020 ◽

Author(s):

Ladislaus Banyai

Keyword(s):

Magnetic Field ◽

Mean Field Theory ◽

Mean Field ◽

Meissner Effect ◽

Transverse Current ◽

Self Consistent ◽

Full Compensation ◽

London Equation ◽

Current Interaction ◽

Constant External Magnetic Field

We show that the implementation of the 1/c² transverse current-current interaction between electrons into the standard self-consistent electron BCS model in bulk under thermal equilibrium ensures in the stable superconductive phase the full compensation of a constant external magnetic field by the internal magnetic field created by the electrons i.e. one has an ideal diamagnet. However, no proof of the phenomenological London equation emerges within the bulk approach.

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