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arXiv · 2510.12554

Conductance Plateaus at Quantum Hall Integer Filling Factors in Germanium Quantum Point Contacts

Karina Hudson·Davide Costa·Davide Degli Esposti·Lucas E. A. Stehouwer·Giordano Scappucci
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Abstract

Constricting transport through a one-dimensional quantum point contact in the quantum Hall regime enables gate-tunable selection of the edge modes propagating between voltage probe electrodes. Here we investigate the quantum Hall effect in a quantum point contact fabricated on low disorder strained germanium quantum wells. For increasing magnetic field, we observe Zeeman spin-split 1D ballistic hole transport evolving to integer quantum Hall states, with well-defined quantised conductance increasing in multiples of $e^2/h$ down to the first integer filling factor $\nu=1$. These results establish strained germanium as a viable platform for complex experiments probing many-body states and quantum phase transitions.

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Karina Hudson, Davide Costa, Davide Degli Esposti, Lucas E. A. Stehouwer, Giordano Scappucci. 2025-10-14. Conductance Plateaus at Quantum Hall Integer Filling Factors in Germanium Quantum Point Contacts. https://arxiv.org/abs/2510.12554

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