Data for Paper "Critical phenomenon of the layered chiral helimagnetic YbNi3Al9"

Single-crystals of YbNi3Al9were grown by the self-flux technique method using excessive Al as a flux. Powders of Yb (purity 3N), Ni (4N), and Al (5N)with a ratio of Yb: Ni: Al = 1: 3: 20 were sealed in a vacuumed quartz tube, and heated to 1173 K. After hold for 12 h, the temperature was cooled to 973 K at a rate of 2 K h−1 . The excess flux was removed by centrifugation at 973 K. Finally, the sample was soaked in hydrochloric acid to exclude extra flux. The chemical compositions of the single crystal were carefully checked by energy dispersive x-ray (EDX)spectrometry. The crystal structure and orientation were determined by x-ray diffraction (XRD) using high-intensity graphite monochromatized Cu Kα radiation. The single crystals were ground into powder to gain the powder XRD pattern, which was refined by the Rietveld method. The magnetization was measured using a Quantum Design vibrating sample magnetometer(SQUID-VSM). To ensure precise field and magnetization, the data was collected after relaxing for 2 min with a no-overshoot mode. In particular, when measuring the initial isothermal magnetization, the sample was cooled to the target temperature under zero field after heated above TC adequately for 10 min.