CONTROLLING COUPLINGS BETWEEN QUANTUM DOTS IN A QUANTUM DOT ARRAY

摘要

A method of controlling coupling of at least two quantum dots in a quantum dot array is described, wherein the method comprises: determining virtual gates for the quantum dots based on first crosstalk contributions of physical gates to dot potentials of quantum dots in the quantum dot array, a virtual gate voltage defining a linear combination of physical gate voltages to be applied to the physical gates for controlling at least one dot potential of a quantum dot or for controlling a coupling of at least two quantum dots in the quantum dot array, while at least partially compensating dot potential crosstalk due to the first crosstalk contributions; determining second crosstalk contributions of the virtual gates to a coupling between one or more pairs of quantum dots in the quantum dot array, the determining including determining partial derivatives of couplings between pairs of quantum dots in the quantum dot array with respect to the virtual gate voltages; determining enhanced virtual gates for the quantum dots based on the second crosstalk contributions, an enhanced virtual gate voltage defining a linear combination of the virtual gate voltages for controlling at least one dot potential or a coupling of a pair of quantum dots in the quantum dot array, while at least partially compensating coupling crosstalk due to the second crosstalk contributions; and, controlling the coupling of at least two quantum dots in the quantum dot array based on at least one of the enhanced virtual gates, the controlling including using the at least one of the enhanced virtual gates to tune the coupling of the at least two quantum dots to a target value.