23 research outputs found
Two-step antiferromagnetic transition and moderate triangular frustration in Li2Co(WO4)2
We present a detailed investigation of the magnetic properties of the
spin- system LiCo(WO) by means of magnetic
susceptibility and specific heat. Our experimental results show that in
LiCo(WO) a short-range antiferromagnetic (AFM) correlations appear
near 11 K and two successive long-range AFM phase
transitions are observed at T 9 K and T 7 K. The
frustration factor, /T3, indicates that the
system is moderately frustrated, which is identifiable by the broken triangular
symmetry within both - and -planes for the triclinic crystal structure.
The magnetic isotherm at temperatures below T shows a field-induced
spin-flop transition, and a complete H-T phase diagram for the two-step AFM
system is mapped. ~ band structure calculations suggest that the
strongest exchange coupling does not correspond to the shortest Co-Co distance
along the -axis, but rather along the diagonal direction through a
Co-O-W-O-Co super-superexchange path within the -planeComment: 7 Pages, 10 Figure
Crystal Growth Of Dirac Semimetal Zrsis With High Magnetoresistance And Mobility
High quality single crystal ZrSiS as a theoretically predicted Dirac semimetal has been grown successfully using a vapor phase transport method. The single crystals of tetragonal structure are easy to cleave into perfect square-shaped pieces due to the van der Waals bonding between the sulfur atoms of the quintuple layers. Physical property measurement results including resistivity, Hall coefficient (RH), and specific heat are reported. The transport and thermodynamic properties suggest a Fermi liquid behavior with two Fermi pockets at low temperatures. At T = 3 K and magnetic field of H||c up to 9 Tesla, large magneto-resistance up to 8500% and 7200% for I|| (100) and I|| (110) were found. Shubnikov de Haas (SdH) oscillations were identified from the resistivity data, revealing the existence of two Fermi pockets at the Fermi level via the fast Fourier transform (FFT) analysis. The Hall coefficient (RH) showed hole-dominated carriers with a high mobility of 3.05 × 104 cm2 V-1 s-1 at 3 K. ZrSiS has been confirmed to be a Dirac semimetal by the Dirac cone mapping near the X-point via angle resolved photoemission spectroscopy (ARPES) with a Dirac nodal line near the Fermi level identified using scanning tunneling spectroscopy (STS)