Chains of semiconductor quantum dots coupled via superconductors

Integrated quantum circuit architecture comprising an integrated quantum dot structure that comprises:

• a semiconductor extending in a first direction and hosting a first quantum dot, a second quantum dot, a third quantum dot and a fourth quantum dot;
• a first superconductor extending in a second direction substantially perpendicular to the first direction, the first superconductor being partly formed on top of a first region of the semiconductor, the first region being located in between the first and second quantum dots with respect to the first direction;
• a first control gate configured to control a first coupling between the first and second quantum dots, the first coupling being mediated by one or more electrons and involving the first superconductor;
• a second superconductor extending in the second direction, the second superconductor being partly formed on top of a second region of the semiconductor, the second region being located in between the third and fourth quantum dots with respect to the first direction;
• a second control gate configured to control a second coupling between the third and fourth quantum dots, the second coupling being mediated by one or more electrons and involving the second superconductor;
• and
• an electrostatic control gate configured to control a tunnel coupling amplitude of single-electron tunnelling between the second quantum dot and the third quantum dot;
• wherein the integrated quantum circuit architecture further comprises:
• a Josephson junction;
• and
• a capacitor element;
• wherein the first superconductor and the second superconductor are connected to each other so as to form the Josephson junction,
• wherein the Josephson junction is configured to exhibit a Josephson energy,
• wherein the capacitor element is configured to provide a capacitive coupling,
• wherein a loop is formed by the first superconductor, the Josephson junction, the second superconductor, and the quantum dots.