Valley-filling instability and critical magnetic field for interaction-enhanced Zeeman response in doped WSe2 monolayers

AbstractCarrier-doped transition metal dichalcogenide (TMD) monolayers are of great interest in valleytronics due to the large Zeeman response (g-factors) in these spin-valley-locked materials, arising from many-body interactions. We develop an ab initio approach based on many-body perturbation theory to compute the interaction-enhanced g-factors in carrier-doped materials. We show that the g-factors of doped WSe2 monolayers are enhanced by screened-exchange interactions resulting from magnetic-field-induced changes in band occupancies. Our interaction-enhanced g-factors g* agree well with experiment. Unlike traditional valleytronic materials such as silicon, the enhancement in g-factor vanishes beyond a critical magnetic field Bc achievable in standard laboratories. We identify ranges of g* for which this change in g-factor at Bc leads to a valley-filling instability and Landau level alignment, which is important for the study of quantum phase transitions in doped TMDs. We further demonstrate how to tune the g-factors and optimize the valley-polarization for the valley Hall effect.

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Theoretical Derivation of Critical Current Density and Critical Magnetic Field Considering Many-Body Interactions of Magnetic Flux Quanta

10.20944/preprints202105.0227.v1 ◽

2021 ◽

Author(s):

Shinichi Ishiguri

Keyword(s):

Magnetic Field ◽

Critical Temperature ◽

Magnetic Flux ◽

Critical Current Density ◽

Critical Current ◽

Current Density ◽

Critical Magnetic Field ◽

Many Body ◽

Magnetic Flux Quantum ◽

Many Body Interactions

To clarify the relationships among critical temperature, critical magnetic field, and critical current density, this paper describes many-body interactions of quantum magnetic fluxes (i.e., vortices) and calculates pinning-related critical current density. All calculations are analytically derived, without numerical or fitting methods. After calculating a magnetic flux quantum mass, we theoretically obtain the critical temperature in a many-body interaction scenario (which can be handled by our established method). We also derive the critical magnetic field and inherent critical current density at each critical temperature. Finally, we determine the pinning-related critical current density with self-fields. The relationships between the critical magnetic field and critical temperature, inherent critical current density and critical temperature, and pinning critical current density and self-magnetic field were consistent with experimental observations. From the critical current density and critical magnetic field, we clarified the magnetic field transition. It appears that a magnetic flux quantum collapses when the lattice of magnetic flux quanta melts. Our results, combined with our previously published papers, provide a comprehensive understanding of the transition points in high-Tc cuprates.

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Thermal Entanglement and Critical Behavior of Magnetic Properties on a Triangulated Kagomé Lattice

Acta Polytechnica ◽

10.14311/1344 ◽

2011 ◽

Vol 51 (2) ◽

Author(s):

N. Ananikian ◽

L. Ananikyan ◽

L. Chakhmakhchyan ◽

A. Kocharian

Keyword(s):

Magnetic Field ◽

Heisenberg Model ◽

Quantum Phase Transitions ◽

Exchange Interactions ◽

Effective Field ◽

Threshold Temperature ◽

Kagome Lattice ◽

Thermal Entanglement ◽

Kagomé Lattice ◽

Bogoliubov Inequality

The equilibrium magnetic and entanglement properties in a spin-1/2 Ising-Heisenberg model on a triangulated Kagomé lattice are analyzed by means of the effective field for the Gibbs-Bogoliubov inequality. The calculation is reduced to decoupled individual (clusters) trimers due to the separable character of the Ising-type exchange interactions between the Heisenberg trimers. The concurrence in terms of the three qubit isotropic Heisenberg model in the effective Ising field in the absence of a magnetic field is non-zero. The magnetic and entanglement properties exhibit common (plateau, peak) features driven by a magnetic field and (antiferromagnetic) exchange interaction. The (quantum) entangled and non-entangled phases can be exploited as a useful tool for signalling the quantum phase transitions and crossovers at finite temperatures. The critical temperature of order-disorder coincides with the threshold temperature of thermal entanglement.

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HALL RESISTANCE AND MANY-BODY EFFECTS IN A PARABOLIC WELL

International Journal of Modern Physics B ◽

10.1142/s0217979207043099 ◽

2007 ◽

Vol 21 (08n09) ◽

pp. 1502-1506

Author(s):

A. M. ORTIZ DE ZEVALLOS ◽

N. C. MAMANI ◽

G. M. GUSEV ◽

A. A. QUIVY ◽

T. E. LAMAS ◽

...

Keyword(s):

Magnetic Field ◽

Critical Magnetic Field ◽

Hall Resistance ◽

Charge Redistribution ◽

Many Body ◽

Strong Variation ◽

Exchange Correlation ◽

Impurity Layer ◽

Hall Effect Measurements ◽

A Charge

We report on Hall effect measurements in 1000-4000 Åwide AlxGax-1As parabolic wells with quasi-two-dimensional electrons and holes in the presence of a perpendicular magnetic field. Above a critical magnetic field B > 3T, the Hall resistance is found to increase when temperature decreases. We attribute such an enhanced Hall slope to the variation of the carrier density. The Hartree and exchange-correlation terms produce a strong variation of the potential well shap: the width of the electronic and hole slabs shrinks as magnetic field increases, which in turn leads to a charge redistribution between the well and impurity layer.

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Data-Driven Many-Body Models with Chemical Accuracy for CH4/H2O Mixtures

10.26434/chemrxiv.13013057 ◽

2020 ◽

Author(s):

Marc Riera ◽

Alan Hirales ◽

Raja Ghosh ◽

Francesco Paesani

Keyword(s):

Liquid Phase ◽

Quantitative Description ◽

Liquid Mixtures ◽

Many Body ◽

Energy Functions ◽

Potential Energy Functions ◽

Dynamics Simulations ◽

Body Potential ◽

Small Clusters ◽

Many Body Interactions

<div> <div> <div> <p>Many-body potential energy functions (PEFs) based on the TTM-nrg and MB-nrg theoretical/computational frameworks are developed from coupled cluster reference data for neat methane and mixed methane/water systems. It is shown that that the MB-nrg PEFs achieve subchemical accuracy in the representation of individual many-body effects in small clusters and enables predictive simulations from the gas to the liquid phase. Analysis of structural properties calculated from molecular dynamics simulations of liquid methane and methane/water mixtures using both TTM-nrg and MB-nrg PEFs indicates that, while accounting for polarization effects is important for a correct description of many-body interactions in the liquid phase, an accurate representation of short-range interactions, as provided by the MB-nrg PEFs, is necessary for a quantitative description of the local solvation structure in liquid mixtures. </p> </div> </div> </div>

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Fast (Parallel) Algorithms for Spherical Transforms and Many-Body Interactions with Applications in Electrostratics, Image Processing and Chemistry

10.21236/ada387330 ◽

2001 ◽

Author(s):

S. L. Johnsson ◽

Dragan Mirkovic

Keyword(s):

Image Processing ◽

Parallel Algorithms ◽

Many Body ◽

Spherical Transforms ◽

Many Body Interactions

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Magnetic Field- and Pressure-Induced Quantum Phase Transitions in NH4CuCl3

Progress of Theoretical Physics Supplement ◽

10.1143/ptps.159.241 ◽

2005 ◽

Vol 159 ◽

pp. 241-245 ◽

Cited By ~ 3

Author(s):

Masashi Fujisawa ◽

Budhy Kurniawan ◽

Toshio Ono ◽

Hidekazu Tanaka

Keyword(s):

Magnetic Field ◽

Phase Transitions ◽

Quantum Phase Transitions ◽

Quantum Phase

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Localization and many-body interactions in the quantum Hall effect determined by polarized optical emission

Physical Review B ◽

10.1103/physrevb.44.4006 ◽

1991 ◽

Vol 44 (8) ◽

pp. 4006-4009 ◽

Cited By ~ 41

Author(s):

B. B. Goldberg ◽

D. Heiman ◽

M. Dahl ◽

A. Pinczuk ◽

L. Pfeiffer ◽

...

Keyword(s):

Hall Effect ◽

Quantum Hall Effect ◽

Quantum Hall ◽

Optical Emission ◽

Many Body ◽

Many Body Interactions

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Enhanced critical magnetic field for monoatomic-layer superconductor by Josephson junction steps

Physical Review B ◽

10.1103/physrevb.103.085416 ◽

2021 ◽

Vol 103 (8) ◽

Author(s):

Fumikazu Oguro ◽

Yudai Sato ◽

Kanta Asakawa ◽

Masahiro Haze ◽

Yukio Hasegawa

Keyword(s):

Magnetic Field ◽

Josephson Junction ◽

Critical Magnetic Field

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Interaction between Different Kinds of Quantum Phase Transitions

Quantum Reports ◽

10.3390/quantum3020015 ◽

2021 ◽

Vol 3 (2) ◽

pp. 253-261

Author(s):

Angel Ricardo Plastino ◽

Gustavo Luis Ferri ◽

Angelo Plastino

Keyword(s):

Phase Transitions ◽

Nuclear Physics ◽

Body Problem ◽

Quantum Phase Transitions ◽

Quantum Phase ◽

Exactly Solvable Models ◽

Solvable Models ◽

Many Body ◽

Pairing Interaction ◽

Exactly Solvable

We employ two different Lipkin-like, exactly solvable models so as to display features of the competition between different fermion–fermion quantum interactions (at finite temperatures). One of our two interactions mimics the pairing interaction responsible for superconductivity. The other interaction is a monopole one that resembles the so-called quadrupole one, much used in nuclear physics as a residual interaction. The pairing versus monopole effects here observed afford for some interesting insights into the intricacies of the quantum many body problem, in particular with regards to so-called quantum phase transitions (strictly, level crossings).

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