Possible intermediate quantum spin liquid phase in α-RuCl3 under high magnetic fields up to 100 T

• Published in: Nature communications Vol. 14; no. 1; pp. 5613 - 7
• Main Authors: Zhou, Xu-Guang, Li, Han, Matsuda, Yasuhiro H., Matsuo, Akira, Li, Wei, Kurita, Nobuyuki, Su, Gang, Kindo, Koichi, Tanaka, Hidekazu
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 12.09.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 639/766/119/2795; 639/766/119/997; 639/766/119/999; Humanities and Social Sciences; Liquid phases; Magnetic fields; Magnetic transitions; Magnetization; Magnets; multidisciplinary; Phase diagrams; Phase transitions; Ruthenium trichloride; Science; Science (multidisciplinary); Spin liquid
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-41232-7

Pursuing the exotic quantum spin liquid (QSL) state in the Kitaev material α -RuCl 3 has intrigued great research interest recently. A fascinating question is on the possible existence of a field-induced QSL phase in this compound. Here we perform high-field magnetization measurements of α -RuCl 3 up to 102 T employing the non-destructive and destructive pulsed magnets. Under the out-of-plane field along the c * axis (i.e., perpendicular to the honeycomb plane), two quantum phase transitions are uncovered at respectively 35 T and about 83 T, between which lies an intermediate phase as the predicted QSL. This is in sharp contrast to the case with in-plane fields, where a single transition is found at around 7 T and the intermediate QSL phase is absent instead. By measuring the magnetization data with fields tilted from the c * axis up to 90° (i.e., in-plane direction), we obtain the field-angle phase diagram that contains the zigzag, paramagnetic, and QSL phases. Based on the K - J -Γ- Γ ′ model for α -RuCl 3 with a large Kitaev term we perform density matrix renormalization group simulations and reproduce the quantum phase diagram in excellent agreement with experiments. Recent theoretical work predicted an intermediate quantum spin liquid state in α -RuCl 3 in out-of-plane magnetic field. Zhou et al. present experimental evidence for this state between two magnetic transitions identified by high-field magnetization measurements.