Cross-Platform Autonomous Control of Minimal Kitaev Chains

Contemporary quantum devices are reaching new limits in size and complexity, allowing for the experimental exploration of emergent quantum modes. However, this increased complexity introduces significant challenges in device tuning and control. Here, we demonstrate autonomous tuning of emergent Poor Man’s Majorana zero modes in a minimal realization of a Kitaev chain. We achieve this task using cross-platform transfer learning. First, we train a tuning model on a theory model. Next, we retrain it using a Kitaev chain realization in a two-dimensional electron gas. Finally, we apply this model to tune a Kitaev chain realized in quantum dots coupled through a semiconductor-superconductor section in a one-dimensional nanowire. Utilizing a convolutional neural network, we predict the tunneling and Cooper pair splitting rates from differential conductance measurements, employing these predictions to adjust the electrochemical potential to a Poor Man’s Majorana sweet spot. The algorithm successfully converges to an immediate vicinity of a sweet spot (within <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mrow> <a:mo>±</a:mo> <a:mn>1.5</a:mn> <a:mspace width="0.16em"/> <a:mi mathvariant="normal">m</a:mi> <a:mi mathvariant="normal">V</a:mi> </a:mrow> </a:math> in 67.6% of attempts and within <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"> <e:mrow> <e:mo>±</e:mo> <e:mn>4.5</e:mn> <e:mspace width="0.16em"/> <e:mi mathvariant="normal">m</e:mi> <e:mi mathvariant="normal">V</e:mi> </e:mrow> </e:math> in 80.9% of cases), typically finding a sweet spot in 45 min or less. This advancement is a stepping stone toward autonomous tuning of emergent modes in interacting systems, and toward foundational tuning machine learning models that can be deployed across a range of experimental platforms.