Silicon quantum device structures defined by metallic structures

Abstract

A silicon-based quantum device is provided. The device comprises: a first metallic structure (); a second metallic structure () laterally separated from the first metallic structure; and an L-shaped elongate channel () defined by the separation between the first and second metallic structures; wherein the elongate channel has a vertex () connecting two elongate parts of the elongate channel. The device further comprises: a third metallic structure (), mediator gate, positioned in the elongate channel; a fourth metallic structure () forming a first barrier gate, arranged at a first end of the third metallic structure; and a fifth metallic structure () forming a second barrier gate arranged at a second end of the third metallic structure. The first, second, third, fourth and fifth metallic structures are configured for connection to first, second, third, fourth and fifth electric potentials respectively. The first, second, fourth and fifth electric potentials are controllable to define an electrical potential well to confine quantum charge carriers in an elongate quantum dot beneath the elongate channel. The fourth and fifth electric potentials and the position of the fourth and fifth metallic structures define first and second ends of the elongate channel respectively. The width of the electrical potential well is defined by the position of the first and second metallic structures and their corresponding electric potentials; and the length of the electrical potential well is defined by the position of the fourth and fifth metallic structures and their corresponding electric potentials. The third electric potential is controllable to adjust quantum charge carrier energy levels in the electrical potential well.