Quantum Transport and Apparent Work Function Distributions of Atomic Contacts via a 3D-Printed High-Vacuum Platform
We present a low-cost, 3D-printed high-vacuum platform integrating a mechanically controllable break-junction system and a custom logarithmic amplifier for room-temperature quantum transport measurements. Using copper as a highly reactive test case, we successfully resolve the $1G_0$ conductance quantum under both high vacuum and anhydrous glycerol, demonstrating the effectiveness of these environments against rapid atmospheric oxidation. In parallel, utilizing gold as a robust benchmark, we systematically extract the apparent work function ($ϕ$) from thousands of tunneling traces across ambient air, vacuum, and glycerol. Our analysis demonstrates that the statistical distribution of $ϕ$ rigorously follows a non-central chi-square distribution. The obtained gold work functions match existing literature across all environments. Although lower than bulk values, they perfectly align with theoretical models accounting for atomic-scale roughness, apex geometry, and environmental adsorbates. Ultimately, this methodology establishes an accessible and reproducible framework for systematic nanoscale research on reactive materials.