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Related papers: Majorana Diagrammatics for Quantum Spin-1/2 Models

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To check the reliability of the Majorana representation of quantum spin systems, we use it to compute the ground state energy of an antiferromagnetic spin 1/2 chain to one loop order. We find a very small one loop correction of the mean…

Strongly Correlated Electrons · Physics 2008-02-03 D. Foerster

Achieving long-range ferrimagnetic order in purely organic systems remains a major challenge in molecular magnetism. Here we report the synthesis and characterization of heterospin-coupling motifs, formed by covalently linking spin-1/2 and…

Mesoscale and Nanoscale Physics · Physics 2026-04-10 Elia Turco , Fupeng Wu , Annika Bernhardt , Nils Krane , Ji Ma , Roman Fasel , Michal Juriček , Xinliang Feng , Pascal Ruffieux

In this study, a spin-1/2 extended anisotropic XY chain has been introduced in which both time reversal and SU(2) symmetries are broken but $Z_2$ symmetry is preserved. Magnetic and topological phase diagrams in the parameter space have…

Mesoscale and Nanoscale Physics · Physics 2024-02-19 Rakesh Kumar Malakar , Asim Kumar Ghosh

Motivated by the unexpected Monte Carlo results as well as the theoretical proposal of a large correction to scaling for the critical theory of the 2-d staggered-dimer spin-1/2 Heisenberg model on the square lattice, we study the phase…

Strongly Correlated Electrons · Physics 2012-06-19 M. -T. Kao , D. -J. Tan , F. -J. Jiang

We study an extended spin-$1/2$ antiferromagnetic Heisenberg model on the triangular lattice, which includes both nearest- and next-nearest-neighbor interactions, as well as a scalar chiral term. This model exhibits a rich phase diagram…

Strongly Correlated Electrons · Physics 2025-08-26 Markus Drescher , Laurens Vanderstraeten , Roderich Moessner , Frank Pollmann

Holographic quantum error-correcting codes have been proposed as toy models that describe key aspects of the AdS/CFT correspondence. In this work, we introduce a versatile framework of Majorana dimers capturing the intersection of…

High Energy Physics - Theory · Physics 2019-11-12 Alexander Jahn , Marek Gluza , Fernando Pastawski , Jens Eisert

Disordered quantum antiferromagnets in two-dimensional compounds have been a focus of interest in the last years due to their exotic properties. However, with very few exceptions, the ground states of the corresponding Hamiltonians are…

Quantum Gases · Physics 2017-06-07 A. Yuste , M. Moreno-Cardoner , A. Sanpera

A novel quantum representation of lattice spin operators (LSOs) is achieved by mapping quantum spins onto their classical analogues for spin size $S=1/2$ and $S=1$. The "braket" representations of LSOs are attained thanks to a profound…

Soft Condensed Matter · Physics 2025-04-17 Maseim Bassis Kenmoe

Magnetization of a spin1/2 set is determined by means of their individual wave function. The theoretical treatment based on the fundamental axioms of quantum mechanics and solving explicitly Schr\"odinger equation gives the evolution of…

Quantum Physics · Physics 2023-08-22 Tarek Khalil , Daniel Grucker

The emergence of a collective behavior in a many-body system is responsible of the quantum criticality separating different phases of matter. Interacting spin systems in a magnetic field offer a tantalizing opportunity to test different…

Quantum Physics · Physics 2023-02-17 Michele Grossi , Oriel Kiss , Francesco De Luca , Carlo Zollo , Ian Gremese , Antonio Mandarino

Using the formal languages Schoonschip and Form, we have developed general codes that are able to carry out all the algebraic manipulations needed to perform analytic lattice calculations, starting from the elementary building blocks…

High Energy Physics - Lattice · Physics 2007-05-23 Stefano Capitani , Giancarlo Rossi

We present a general formalism that allows for the computation of large-order renormalized expansions in the spacetime representation, effectively doubling the numerically attainable perturbation order of renormalized Feynman diagrams. We…

Strongly Correlated Electrons · Physics 2020-11-12 Riccardo Rossi , Fedor Simkovic , Michel Ferrero

We present an exactly solvable spin-3/2 model defined on a pentacoordinated three-dimensional graphite lattice, which realizes a novel quantum spin liquid with second-order topology. The exact solutions are described by Majorana fermions…

Strongly Correlated Electrons · Physics 2020-06-01 Y. X. Zhao , Y. Lu , Shengyuan A. Yang

Determining phase diagrams and phase transitions semi-automatically using machine learning has received a lot of attention recently, with results in good agreement with more conventional approaches in most cases. When it comes to more…

Disordered Systems and Neural Networks · Physics 2019-12-04 Hugo Théveniaut , Fabien Alet

We use the spin functional renormalization group to investigate the $J_1$-$J_2$ quantum Heisenberg model on a square lattice. By incorporating sum rules associated with the fixed length of the spin operators as well as the nontrivial…

Strongly Correlated Electrons · Physics 2024-05-08 Andreas Rückriegel , Dmytro Tarasevych , Peter Kopietz

We describe random loop models and their relations to a family of quantum spin systems on finite graphs. The family includes spin 1/2 Heisenberg models with possibly anisotropic spin interactions and certain spin 1 models with…

Mathematical Physics · Physics 2013-08-23 Daniel Ueltschi

Many of the exciting features of the Standard Model of the elementary particles are inherently non-perturbative. A theoretical understanding of many physics aspects beyond the Standard Model of elementary particles also requires a…

High Energy Physics - Lattice · Physics 2024-02-12 Navdeep Singh Dhindsa

We introduce a variational manifold of simple tensor network states for the study of a family of constrained models that describe spin-1/2 systems as realized by Rydberg atom arrays. Our manifold permits analytical calculation via…

Quantum Physics · Physics 2024-05-13 Joey Li , Giuliano Giudici , Hannes Pichler

We report recent progress in the study of a particular class of spin 1/2 XXZ model on two-dimensional lattices with frustrated diagonal and unfrustrated off-diagonal interactions. Quantum Monte Carlo simulations can be constructed without a…

Disordered Systems and Neural Networks · Physics 2009-11-11 Roger G. Melko

We consider the quantum theory of the Lorentzian fermionic differential forms and the corresponding bi-spinor quantum fields, which are the expansion coefficients of the forms in the bi-spinor basis of Becher and Joos [7]. The canonical…

High Energy Physics - Phenomenology · Physics 2020-02-05 Alex Jourjine