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Hu, Zhixiang

Publications and source records attributed to Hu, Zhixiang.

24 records · Page 2

Anomalous Hall effect in the weak-itinerant ferrimagnet FeCr 2 Te 4

In this study, we carried out a comprehensive study of electronic transport, thermal, and thermodynamic properties in Fe Cr 2 Te 4 single crystals. It exhibits bad-metallic behavior and anomalous Hall effect (AHE) below a weak-itinerant paramagnetic-to-ferrimagnetic transition T c ~ 123 K. The linear scaling between the anomalous Hall resistivity ρ x y and the longitudinal resistivity ρ x x implies that the AHE in Fe Cr 2 Te 4 is most likely dominated by an extrinsic skew-scattering mechanism rather than an intrinsic KL or an extrinsic side-jump mechanism, which is supported by our Berry phase calculations.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

High Fermi velocities and small cyclotron masses in LaAlGe

Here, we report quantum oscillation measurements of LaAlGe, a Lorentz-violating type-II Weyl semimetal with tilted Weyl cones. Very small quasiparticle masses and very high Fermi velocities were detected at the Fermi surface. Whereas three main frequencies have been observed, the angular dependence of two Fermi surface sheets indicates possible two-dimensional (2D) character despite the absence of the 2D structural features such as van der Waals bonds. Such conducting states may offer a good platform for low-dimensional polarized spin current in magnetic RAlGe (R = Ce, Pr) materials.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Three-dimensional Ising ferrimagnetism of Cr-Fe-Cr trimers in FeCr2Te4

We carried out a comprehensive study of magnetic critical behavior in single crystals of ternary chalcogenide Fe Cr 2 Te 4 that undergoes a ferrimagnetic transition below T c ~ 123 K. Detailed critical behavior analysis and scaled magnetic entropy change indicate a second-order ferrimagnetic transition. Critical exponents β = 0.30 ( 1 ) with T c = 122.4 ( 5 ) K , γ = 1.22 ( 1 ) with T c = 122.8 ( 1 ) K , and δ = 4.24 ( 2 ) at T c ~ 123 K suggest that the spins approach the three-dimensional Ising ( β = 0.325 , γ = 1.24 , and δ = 4.82 ) model coupled with attractive long-range interactions between spins that decay as J ( r ) ≈ r - 4.88 . Our results suggest that the ferrimagnetism in Fe Cr 2 Te 4 is due to itinerant ferromagnetism among the antiferromagnetically coupled Cr-Fe-Cr trimers.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Anisotropic magnetocaloric effect and critical behavior in CrSbSe3

In this work, we report anisotropic magnetocaloric effect and critical behavior in a quasi-one-dimensional ferromagnetic CrSbSe 3 single crystal. The maximum magnetic entropy change - Δ S M max is 2.16 J kg - 1 K - 1 for the easy a axis (2.03 J kg - 1 K - 1 for the hard b axis) and the relative cooling power RCP is 163.1 J kg - 1 for the easy a axis (142.1 J kg - 1 for the hard b axis) near T c with a magnetic field change of 50 kOe. The magnetocrystalline anisotropy constant K u is estimated to be 148.5 kJ m - 3 at 10 K, decreasing to 39.4 kJ m - 3 at 70 K. The rescaled Δ S M ( T , H ) curves along all three axes collapse onto a universal curve, respectively, confirming the second-order ferromagnetic transition. Further critical behavior analysis around T c ~ 70 K gives that the critical exponents β = 0.26 ( 1 ) , γ = 1.32 ( 2 ) , and δ = 6.17 ( 9 ) for H ∥ a , while β = 0.28 ( 2 ) , γ = 1.02 ( 1 ) , and δ = 4.14 ( 16 ) for H ∥ b . The determined critical exponents suggest that the anisotropic magnetic coupling in CrSbSe 3 is strongly dependent on orientations of the applied magnetic field.

2-dimensional systems↗

Three-dimensional Fermi surface and small effective masses in Mo 8 Ga 41

We report Fermi surface characteristics of Mo 8 Ga 41 , a two-gap superconductor with critical temperature T c ~10 K, obtained from quantum oscillation measurements. Four major frequencies have been observed with relatively small quastiparticle masses. Angular dependence of major frequencies indicates three-dimensional Fermi surface sheets. This argues for a relatively isotropic superconducting state and, given its relatively high T c , shows that a search for new materials in this class could be of interest for superconducting wire applications.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗