Two-dimensional magnetic systems

• Grant number: 10/00479-6
• Support type: Research Grants - Young Investigators Grants
• Duration: September 01, 2010 - August 31, 2015
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Ricardo Luis Doretto
• Grantee: Ricardo Luis Doretto
• Home Institution: Instituto de Física Gleb Wataghin (IFGW). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated scholarship(s): 10/16370-3 - Two-dimensional magnetic systems, BP.JP

Abstract

This project will be devoted to the study of two classes of low dimensional magnetic systems: the two-dimensional electron gas under strong perpendicular and uniform magnetic field and insulating quantum antiferromagnets. In the first case, we will concentrate on the bilayer quantum Hall system at total filling factor one and on the quantum Hall system at total filling factor zero observed in graphene. The main idea is to describe the magnetic exciton condensate phase, which might be realized in such systems, within anon-perturbative bosonization method that we have recently developed. In the second case, we will basically focus on paramagnetic quantum phases. Here we intend to generalize the so-called bondoperator formalism, which has been used to describe valence bond solid (VBS) phases, in order to study the following problems: the Néel-VBS quantum phase transition, the spin liquid phases of the Heisenberg model on a kagome lattice, and the fate of the local magnetic moments when a Mott insulator is doped. (AU)

Scientific publications

(5)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DORETTO, R. L. Mean-field theory of interacting triplons in a two-dimensional valence-bond solid: Stability and properties of many-triplon states. Physical Review B, v. 102, n. 1 JUL 10 2020. Web of Science Citations: 0.

DORETTO, R. L.; GOERBIG, M. O. Flat-band ferromagnetism and spin waves in topological Hubbard models. Physical Review B, v. 92, n. 24 DEC 18 2015. Web of Science Citations: 8.

DORETTO, R. L. Plaquette valence-bond solid in the square-lattice J(1)-J(2) antiferromagnet Heisenberg model: A bond operator approach. Physical Review B, v. 89, n. 10 MAR 19 2014. Web of Science Citations: 23.

DORETTO, R. L.; SMITH, C. MORAIS; CALDEIRA, A. O. Finite-momentum condensate of magnetic excitons in a bilayer quantum Hall system. Physical Review B, v. 86, n. 3 JUL 26 2012. Web of Science Citations: 5.

DORETTO, R. L.; VOJTA, MATTHIAS. Triangular-lattice anisotropic dimerized Heisenberg antiferromagnet: Stability and excitations of the quantum paramagnetic phase. Physical Review B, v. 85, n. 10, p. 104416, 2012. Web of Science Citations: 9.