Conveyor-mode shuttling in gated Si/SiGe devices enables adiabatic transfer of single electrons, electron patterns and spin qubits confined in quantum dots across several microns with a scalable number of signal lines. To realize their full potential, linear shuttle lanes must connect into a two-dimensional grid with controllable routing. We introduce a T-junction device linking two independently driven shuttle lanes. Electron routing across the junction requires no extra control lines beyond the four channels per conveyor belt. We measure an inter-lane charge transfer fidelity of F=100.0000000−9×10−7+0% at an instantaneous electron velocity of 270mms−1. The filling of 54 quantum dots is controlled by simple atomic pulses, allowing us to swap electron patterns, laying the groundwork for a native spin-qubit SWAP gate. This T-junction establishes a path towards scalable, two-dimensional quantum computing architectures with flexible spin qubit routing for quantum error correction.
@article{arxiv.2601.03942,
title = {Conveyor-mode electron shuttling through a T-junction in Si/SiGe},
author = {Max Beer and Ran Xue and Lennart Deda and Stefan Trellenkamp and Jhih-Sian Tu and Paul Surrey and Inga Seidler and Hendrik Bluhm and Lars R. Schreiber},
journal= {arXiv preprint arXiv:2601.03942},
year = {2026}
}