Strong-randomness infinite-coupling phase in a random quantum spin chain

Autor(es)

Hrahsheh, Fawaz ^[1] ; Hoyos, Jose A. ^[2] ; Narayanan, Rajesh ^[3] ; Vojta, Thomas ^[1]

Afiliação do(s) autor(es)

^[1] Missouri Univ Sci & Technol, Dept Phys, Rolla, MO 65409 - USA

^[2] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[3] Indian Inst Technol Madras, Dept Phys, Chennai 600036, Tamil Nadu - India

• Tipo de documento: Artigo Científico
• Fonte: Physical Review B; v. 89, n. 1 JAN 3 2014.
• Citações Web of Science: 7

Resumo

We study the ground-state phase diagram of the Ashkin-Teller random quantum spin chain by means of a generalization of the strong-disorder renormalization group. In addition to the conventional paramagnetic and ferromagnetic (Baxter) phases, we find a partially ordered phase characterized by strong randomness and infinite coupling between the colors. This unusual phase acts, at the same time, as a Griffiths phase for two distinct quantum phase transitions, both of which are of infinite-randomness type. We also investigate the quantum multicritical point that separates the two-phase and three-phase regions, and we discuss generalizations of our results to higher dimensions and other systems. (AU)

• Processo FAPESP: 13/09850-7 - Disorder, Dynamics, Frustration and Topology in Quantum Condensed Matter
• Beneficiário: José Abel Hoyos Neto
• Modalidade de apoio: Auxílio à Pesquisa - Reunião - Exterior