scholarly journals Entanglement perturbation theory for infinite quasi-1D quantum systems

2015 ◽  
Vol 29 (07) ◽  
pp. 1550042 ◽  
Author(s):  
Lihua Wang ◽  
Sung Gong Chung
Keyword(s):  
Phase Diagram ◽  
Perturbation Theory ◽  
Nearest Neighbor ◽  
Quantum Systems ◽  
Easy Plane ◽  
Heisenberg Chain ◽  
The Third ◽  
Plane Anisotropy ◽  
Improved Accuracy

We develop entanglement perturbation theory (EPT) for infinite Quasi-1D quantum systems. The spin-1/2 Heisenberg chain with ferromagnetic nearest neighbor (NN) and antiferromagnetic next nearest neighbor (NNN) interactions with an easy-plane anisotropy is studied as a prototypical system. The obtained phase diagram is compared with a recent prediction [Phys. Rev. B 81, 094430 (2010)] that dimer and Néel orders appear alternately as the XXZ anisotropy Δ approaches the isotropic limit Δ = 1. The first and second transitions (across dimer, Néel and dimer phases) are detected with improved accuracy at Δ ≈ 0.722 and 0.930. The third transition (from dimer to Néel phases), previously predicted to be at Δ ≈ 0.98, is not detected at this Δ in our method, strongly indicating that the second Néel phase is absent.

scholarly journals COMPETING PHASES IN SPIN-½ J1-J2 CHAIN WITH EASY-PLANE ANISOTROPY

2011 ◽  
Vol 25 (12n13) ◽  
pp. 901-908 ◽  
Author(s):  
MASAHIRO SATO ◽  
SHUNSUKE FURUKAWA ◽  
SHIGEKI ONODA ◽  
AKIRA FURUSAKI
Keyword(s):  
Phase Diagram ◽  
Ground State ◽  
Nearest Neighbor ◽  
Luttinger Liquid ◽  
Rich Variety ◽  
Narrow Region ◽  
Chiral Phases ◽  
Liquid Phases ◽  
Plane Anisotropy ◽  
Xxz Chain

We summarize our theoretical findings on the ground-state phase diagram of the spin-½ XXZ chain having competing nearest-neighbor (J1) and antiferromagnetic next-nearest-neighbor (J2) couplings. Our study is mainly concerned with the case of ferromagnetic J1, and the case of antiferromagnetic J1 is briefly reviewed for comparison. The phase diagram contains a rich variety of phases in the plane of J1/J2 versus the XXZ anisotropy Δ: vector-chiral phases, Néel phases, several dimer phases, and Tomonaga–Luttinger liquid phases. We discuss the vector-chiral order that appears for a remarkably wide parameter space, successive Néel-dimer phase transitions, and an emergent nonlocal string order in a narrow region of ferromagnetic J1 side.

SPIN GAPLESS BOND-ORDERED PHASE IN THE EXTENDED HUBBARD CHAIN WITH SPIN-DEPENDENT REPULSION

2011 ◽  
Vol 25 (27) ◽  
pp. 3555-3568 ◽  
Author(s):  
HANQIN DING ◽  
JUN ZHANG
Keyword(s):  
Phase Diagram ◽  
Renormalization Group ◽  
Weak Coupling ◽  
Nearest Neighbor ◽  
Density Wave ◽  
Spin Density Wave ◽  
Extended Hubbard Model ◽  
Weak Coupling Regime ◽  
One Dimensional ◽  
Plane Anisotropy

Using the field theoretical bosonization and renormalization group techniques, we analytically study quantum phase diagram of a one-dimensional half-filled extended Hubbard model with on-site (U) and spin-dependent nearest-neighbor interactions (V⊥, V‖) in the weak coupling regime. In the case of easy-plane anisotropy (V⊥ > V‖) and at V‖ < U/2, the existence of bond-ordered spin-density-wave phase, corresponding to spin gapless transverse magnetization located on bonds (BSDW±) is shown.

Phase diagram of Ising model (S=1) with easy-plane anisotropy in a magnetic field

1998 ◽  
Vol 24 (9) ◽  
pp. 652-657 ◽  
Author(s):  
A. A. Loginov ◽  
Yu. V. Pereverzev
Keyword(s):  
Magnetic Field ◽  
Phase Diagram ◽  
Ising Model ◽  
Easy Plane ◽  
Plane Anisotropy

Phase diagram of the easy-plane ferromagnetic-antiferromagnetic S=1 Heisenberg chain

2017 ◽  
Vol 523 ◽  
pp. 125-131
Author(s):  
Lihua Pan ◽  
Yu Cao ◽  
Bin Xi ◽  
Yong-Jun Liu
Keyword(s):  
Phase Diagram ◽  
Easy Plane ◽  
Heisenberg Chain

High-field soft-x-ray dichroism of a hard ferrimagnet with easy-plane anisotropy

2021 ◽  
Vol 104 (6) ◽  
Author(s):  
Sh. Yamamoto ◽  
D. I. Gorbunov ◽  
I. F. Diaz-Ortega ◽  
A. Miyata ◽  
T. Kihara ◽  
...  
Keyword(s):  
High Field ◽  
Easy Plane ◽  
X Ray ◽  
Plane Anisotropy

scholarly journals Effective Hamiltonian for a half-filled asymmetric ionic Hubbard chain with alternating on-site interaction

2016 ◽  
Vol 30 (03) ◽  
pp. 1550260 ◽  
Author(s):  
I. Grusha ◽  
M. Menteshashvili ◽  
G. I. Japaridze
Keyword(s):  
Magnetic Field ◽  
Nearest Neighbor ◽  
Effective Hamiltonian ◽  
Heisenberg Chain ◽  
Spin Hamiltonian ◽  
Effective Spin ◽  
One Dimensional ◽  
The One ◽  
Strong Repulsion ◽  
Ionic Hubbard Model

We derive an effective spin Hamiltonian for the one-dimensional half-filled asymmetric ionic Hubbard model (IHM) with alternating on-site interaction in the limit of strong repulsion. It is shown that the effective Hamiltonian is that of a spin S = 1/2 anisotropic XXZ Heisenberg chain with alternating next-nearest-neighbor (NNN) and three-spin couplings in the presence of a uniform and a staggered magnetic field.

Oxygen vacancy migration in CSZ using density functional theory

2008 ◽  
Vol 1122 ◽  
Author(s):  
Byeong-Eon Lee ◽  
Dae-Hee Kim ◽  
Yeong-Cheol Kim
Keyword(s):  
Density Functional Theory ◽  
Oxygen Vacancy ◽  
Density Functional ◽  
Oxygen Vacancies ◽  
Nearest Neighbor ◽  
Functional Theory ◽  
The Third ◽  
Vacancy Migration ◽  
Neighbor Site ◽  
Formation Energies

AbstractWe studied oxygen migration in calcia-stabilized cubic zirconia (CSZ) using density functional theory. A Ca atom was substituted for a Zr atom in a 2×2×2 ZrO2 cubic supercell, and an oxygen vacancy was produced to satisfy the charge neutrality condition. We found that the formation energies of an oxygen vacancy, as a function of its location with respect to the Ca atom, were varied. The relative formation energies of the oxygen vacancies located at the first-, second-, third-, and fourth-nearest-neighbors were 0.0, −0.07, 0.19, and 0.19 eV, respectively. Therefore, the oxygen vacancy located at the second-nearest-neighbor site of the Ca atom was the most favorable, the oxygen vacancy located at the first-nearest-neighbor site was the second most favorable, and the oxygen vacancies at the third- and fourth-nearest-neighbor sites were the least favorable. We also calculated the energy barriers for the oxygen vacancy migration between oxygen sites. The energy barriers between the first and the second nearest sites, the second and third nearest sites, and the third and fourth nearest sites were 0.11, 0.46, and 0.23 eV, respectively. Therefore, the oxygen vacancies favored the first- and second-nearest-neighbor oxygen sites when they drifted under an electric field.

Sign in / Sign up

Export Citation Format

Share Document