2009/11/30 by H. T. Ueda, Hiroaki T Ueda, Keisuke Totsuka +3
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Bose gas #Bose–Einstein condensate #Condensed matter physics #Ferromagnetism #Field (mathematics) #Ground state #Magnetic and transport properties of perovskites and related materials #Magnetic field #Magnetization #Magnon #Multiferroics and related materials #Phase (matter) #Phase diagram #Phase transition #Physics #Quantum #Quantum fluctuation #Quantum mechanics #Quantum phase transition #cond-mat.str-el
paper · pdf · doi:10.1088/1742-6596/200/2/022067
published in Journal of Physics Conference Series 200(2), 022067 (IOP Publishing) · 4pages, 3figures, International Conference on Magnetism (ICM) 2009 (Karlsruhe, Germany, July 26-31, 2009).
openalex publication_date 2010/01/01 · arxiv created 2010/04/16 · arxiv updated 2010/04/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We study high-field phase diagram and low-energy excitations of three-dimensional quantum helimagnets. Slightly below the saturation field, the emergence of magnetic order may be mathematically viewed as Bose-Einstein condensation (BEC) of magnons. The method of dilute Bose gas enables an unbiased quantitative analysis of quantum effects in three-dimensional helimagnets and thereby three phases are found: cone, coplanar fan and an attraction-dominant one. To investigate the last phase, we extend the usual BEC approach so that we can handle 2-magnon bound states. In the case of 2-magnon BEC, the transverse magnetization vanishes and long-range order occurs in the quadrupolar channel (spin-nematic phase). As an application, we map out the phase diagram of a 3D helimagnet which consists of frustrated J 1 - J 2 chains coupled by an interchain interaction J 3 .