Compact silicon qubit cell with embedded readout

Abstract

A quantum device is disclosed having an LC resonator circuit for performing qubit measurement or readout. The device comprises a silicon layer (), a dielectric layer () disposed upon and forming a functional interface with the silicon layer (), a first metallic region () disposed upon the dielectric layer, and a second metallic region () disposed upon the dielectric layerand laterally separated from the first metallic region (). The first and second metallic regions () are arranged to be electrically connected such that a double quantum dot, forming a qubit having a first state and a second state, can be induced beneath the first and second metallic regions () at the functional interface. The double quantum dot provides a capacitor Cin the LC resonator circuit and the capacitance of the double quantum dot is dependent on the state of the qubit. The first metallic region () provides an inductor Lin the LC resonator circuit, and the resonant frequency of the LC resonator circuit is dependent on the state of the qubit such that the state of the qubit can be measured or inferred.