Crystal structure, thermodynamic properties, and adiabatic demagnetization refrigeration (ADR) effect in the spin-7 2 triangular antiferromagnet KBaGd(BO 3 ) 2 are reported. With the average nearest-neighbor exchange coupling of 44 mK, this compound shows magnetic order below T N = 263 mK in zero field. The ADR tests reach the temperature of T min = 122 mK, more than twice lower than T N , along with the entropy storage capacity of 192 mJ K −1 cm −3 and the hold time of more than 8 h in the PPMS setup, both significantly improved compared to the spin-1 2 Yb 3+ analog. We argue that KBaGd(BO 3 ) 2 shows a balanced interplay of exchange and dipolar couplings that together with structural randomness and geometrical frustration shift T min to well below the ordering temperature T N , therefore facilitating the cooling.
Li 2 Sr [MnN] 2 single crystals were successfully grown out of Li-rich flux. The crystal structure was determined by single-crystal x-ray diffraction and revealed almost linear −N − Mn − N − Mn− chains as central structural motif. Tetragonal blocks of air and moisture-sensitive nitridomanganate were employed for electrical transport, heat capacity, and anisotropic magnetization measurements. Both the electronic and magnetic properties are most remarkable, in particular the linear increase of the magnetic susceptibility with temperature that is reminiscent of underdoped cuprate and Fe-based superconductors. Clear indications for antiferromagnetic ordering at T N = 290 K were obtained. Metallic transport behavior is experimentally observed in accordance with electronic band structure calculations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.