Two-dimensional hole gases (2DHGs) confined in Ge/SiGe quantum wells offer a promising platform for exploring low-dimensional spintronic phenomena and valence band dynamics, due to their strong spin-orbit interaction and long spin coherence times. Biaxial compressive strain arising from the lattice mismatch between the Ge well and SiGe barriers defines the fundamental physical properties of the 2DHG. Meanwhile, practical device architectures introduce additional sources of strain. For instance, differential thermal contraction between gate electrodes and the quantum well leads to anisotropic strain, which in turn modulates the electronic structure and transport symmetry. This paper provides a systematic and quantitative investigation into the impact of deliberately in situ applied uniaxial strain on the properties of the 2DHG in Ge/SiGe quantum wells. Using a piezoelectric-based strain cell, uniaxial in-plane strain along the $\left[110\right]$ crystallographic direction is applied and magnetotransport measurements are performed. The results reveal significant anisotropic modulation of the hole effective mass, mobility, and out-of-plane $g$-factor due to strain-induced deformation of the valence band. While the carrier density remains isotropic, the modification of mobility, effective mass, and the out-of-plane $g$-factor show pronounced anisotropy along different crystallographic directions. These findings highlight the critical role of uniaxial strain in shaping the fundamental transport coefficients of Ge/SiGe quantum wells and provide precise experimental benchmarks for strain engineering in future design of high-performance heterostructures and devices.

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• III-V semiconductors
• Quantum wells
• Two-dimensional electron gas
• Two-dimensional electron system
• Resistivity measurements
• Strain engineering