Coupled Spin-Orbit Interactions in Flying Qubit Architectures

Vertical spin-orbit coupling to produce quantum entanglement between electrons confined in quantum dots is investigated for a split-gate double layer heterostructure design. The quantum dots in each active layer may result from quantum point contact fabrication or be generated dynamically using a surface acoustic wave flying qubit approach. Optimization of spin-spin coupling versus all other couplings can set up competing requirements for heterostructure and device fabrication choices. In the present work, a series of active layers: indium antimonide, indium arsenide, indium gallium arsenide, and gallium arsenide, and device architectures is investigated. We find that device architectures that support spin entanglement are within achievable fabrication ranges for the active layer materials investigated.