Possible Bose-Einstein condensation of magnons in a S = 5/2 honeycomb lattice

Abstract

Quantum magnets offer a unique platform for exploring exotic quantum phases and quantum phase transitions through external magnetic fields. A prominent example is the field-induced Bose--Einstein condensation (BEC) of magnons near the saturation field. While this behavior has been observed in low-spin systems, its realization in high-spin, quasi-two-dimensional magnets -- where multiple on-site excitations are possible -- remains exceptionally rare. Here, we report thermodynamic and density functional theory results on single crystals of the honeycomb-lattice antiferromagnet K${}_4$MnMo${}_4$O${}_{15}$ with $S=5/2$. The system undergoes a field-induced transition to a fully polarized state at the critical field ${\mu }_0{H}_{\mathrm{s}}=6.4$~T. Our results reveal possible thermodynamic signatures of magnon BEC, $T_{\mathrm{N}}\sim (H_{\mathrm{s}}-H{)}^{2/d}$ ($d=3$), expanding the purview of BEC-driven quantum criticality to a high-spin, quasi-two-dimensional antiferromagnets with negligibly small anisotropy.

References in corpus (11)

• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Bose-Einstein Condensation in Magnetic Insulators
• Dimensional reduction at a quantum critical point
• Giant Magnetocaloric Effect in Spin Supersolid Candidate Na${}_2$BaCo(PO${}_4$)${}_2$
• Bose-Einstein Condensation of Magnons in Cs2CuCl4
• One-Third Magnetization Plateau with a Preceding Novel Phase in Volborthite
• Field Induced Supersolid Phase in Spin-One Heisenberg Models
• Spin-Nematic and Spin-Density-Wave Orders in Spatially Anisotropic Frustrated Magnets in a Magnetic Field
• Bose-Einstein Condensation of Triplons in Ba3Cr2O8
• Experimental signatures of quantum and topological states in frustrated magnetism
• Development of short and long-range magnetic order in the double perovskite based frustrated triangular lattice antiferromagnet Ba2MnTeO6