Spiral spin liquid noise

• 成果类型: Article
• 署名作者: Takahashi, Hiroto; Hsu, Chun-Chih-Chih; Jerzembeck, Fabian; Murphy, Jack; Ward, Jonathan; Enright, Jack D.; Knapp, Jan; Puphal, Pascal; Isobe, Masahiko; Matsumoto, Yosuke; Takagi, Hidenori; Davis, J. C. Seamus; Blundell, Stephen J.
• 署名单位: University of Oxford; Max Planck Society; University College Cork; Max Planck Society; Cornell University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8754
• DOI: 10.1073/pnas.2422498122
• 发表日期: 2025-03-25
• 关键词: ice

摘要

An emerging concept for identification of different types of spin liquids [C. Broholm et al., Science 367, eaay0668 (2020)] is through the use of spontaneous spin noise [S. Chatterjee, J. F. Rodriguez-Nieva, E. Demler, Phys. Rev. B 99, 104425 (2019)]. Here, we develop spin noise spectroscopy for spin liquid studies by considering Ca10Cr7O28, a material hypothesized to be either a quantum or a spiral spin liquid (SSL). By enhancing techniques introduced for magnetic monopole noise studies [R. Dusad et al., Nature 571, 234-239 (2019)], we measure the time and temperature dependence of spontaneous flux Phi(t, T) and thus magnetization M(t, T) of Ca10Cr7O28 samples. The resulting power spectral density of magnetization noise S-M omega,T reveals intense spin fluctuations with S-M omega,T proportional to omega(-alpha(T)) and 0.84<1.04. Both the variance sigma(2)(M)(T) and the correlation function C-M(t, T) of this spin noise undergo crossovers at a temperature T-& lowast; approximate to 450 mK. While predictions for quantum spin liquids are inconsistent with this phenomenology, those from Monte-Carlo simulations of a two-dimensional (2D) SSL state in Ca10Cr7O28 yield overall quantitative correspondence with the measured frequency and temperature dependences of S-M(omega, T), C(M()t, T), and sigma(2)(M)(T), thus indicating that Ca10Cr7O28 is an SSL.