T. M. LuC. T. HarrisS. –H. HuangY. ChuangJIUN-YUN LICHEE-WEE LIU2019-10-242019-10-24201736951https://scholars.lib.ntu.edu.tw/handle/123456789/428005https://www.scopus.com/inward/record.uri?eid=2-s2.0-85029286339&doi=10.1063%2f1.4990569&partnerID=40&md5=b407ceeed58cffeaffe945ec862d8533We report the measurements of the effective g factor of low-density two-dimensional holes in a Ge quantum well. Using the temperature dependence of the Shubnikov-de Haas oscillations, we extract the effective g factor in a magnetic field perpendicular to the sample surface. Very large values of the effective g factor, ranging from ∼13 to ∼28, are observed in the density range of 1.4×1010 cm-2- 1.4×1011 cm-2. When the magnetic field is oriented parallel to the sample surface, the effective g factor is obtained from a protrusion in the magneto-resistance data that signify full spin polarization. In the latter orientation, a small effective g factor, ∼1.3-1.4, is measured in the density range of 1.5×1010 cm-2- 2×1010 cm-2. This very strong anisotropy is consistent with theoretical predictions and previous measurements in other 2D hole systems, such as InGaAs and GaSb. © 2017 Author(s).Gallium alloys; Germanium; Indium alloys; Magnetic fields; Spin polarization; Temperature distribution; Density range; Effective g-factor; Ge quantum well; Measurements of; Sample surface; Shubnikov de-Haas oscillation; Strong anisotropy; Temperature dependence; Semiconductor quantum wellsjournal article10.1063/1.49905692-s2.0-85029286339