Statistical mechanics of the cluster Ising model

被引：109

作者：

Smacchia, Pietro ^{[1
]}

Amico, Luigi ^{[2
,3
]}

Facchi, Paolo ^{[4
,5
,6
]}

Fazio, Rosario ^{[7
,8
,9
]}

Florio, Giuseppe ^{[6
,10
,11
]}

Pascazio, Saverio ^{[6
,10
,11
]}

Vedral, Vlatko ^{[9
,12
,13
]}

机构：

[1] SISSA, I-34136 Trieste, Italy

[2] Univ Catania, CNR MATIS IMM, I-95125 Catania, Italy

[3] Univ Catania, Dipartimento Fis & Astron, I-95125 Catania, Italy

[4] Univ Bari, Dipartimento Matemat, I-70125 Bari, Italy

[5] Univ Bari, MECENAS, I-70125 Bari, Italy

[6] Ist Nazl Fis Nucl, Sez Bari, I-70126 Bari, Italy

[7] Scuola Normale Super Pisa, NEST, I-56126 Pisa, Italy

[8] CNR, Ist Nanosci, I-56126 Pisa, Italy

[9] Natl Univ Singapore, Ctr Quantum Technol, Singapore 117542, Singapore

[10] Univ Bari, Dipartimento Fis, I-70126 Bari, Italy

[11] Univ Bari, MECENAS, I-70126 Bari, Italy

[12] Natl Univ Singapore, Dept Phys, Singapore 117542, Singapore

[13] Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England

来源：

PHYSICAL REVIEW A | 2011年 / 84卷 / 02期

关键词：

CRITICAL-BEHAVIOR; CONFORMAL-INVARIANCE; 3-SPIN INTERACTIONS; MAGNETIC-FIELD; ENTANGLEMENT; STATE; ENTROPY; SYSTEMS; TRIPLET; 2-SPIN;

D O I：

10.1103/PhysRevA.84.022304

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

We study a Hamiltonian system describing a three-spin-1/2 clusterlike interaction competing with an Ising-like antiferromagnetic interaction. We compute free energy, spin-correlation functions, and entanglement both in the ground and in thermal states. The model undergoes a quantum phase transition between an Ising phase with a nonvanishing magnetization and a cluster phase characterized by a string order. Any two-spin entanglement is found to vanish in both quantum phases because of a nontrivial correlation pattern. Nevertheless, the residual multipartite entanglement is maximal in the cluster phase and dependent on the magnetization in the Ising phase. We study the block entropy at the critical point and calculate the central charge of the system, showing that the criticality of the system is beyond the Ising universality class.

引用

页数：12

共 52 条

[1] ON THE CRITICAL-BEHAVIOR OF THE ISING-MODEL WITH MIXED 2-SPIN AND 3-SPIN INTERACTIONS [J].