Cross-talk Compensation In Quantum Processing Devices
A method for operating a quantum processing device is provided including at least two quantum circuits coupled to a tunable coupler, wherein the quantum circuits are subject to cross-talk, the method including: applying a primary signal to the quantum circuits so as to drive one or more energy transitions between states spanned by the quantum circuits; and applying a compensation signal to the tunable coupler, the compensation signal designed so as to shift at least one state spanned by the quantum circuits, in energy, to compensate for cross-talk between the quantum circuits. Related quantum processing devices and chips are also provided.
Claim CLM-00001. 1. A method of operating a quantum processing device comprising at least two quantum circuits coupled to a tunable coupler,
wherein the quantum circuits are subject to cross-talk, the method comprising:
applying a primary signal to the quantum circuits so as to drive one or more energy transitions between states spanned by the quantum circuits; andapplying a compensation signal to the tunable coupler, the compensation signal designed so as to shift at least one state spanned by the quantum circuits, in energy, to compensate for cross-talk between the quantum circuits, and
wherein the cross-talk between the quantum circuits gives rise to hybridized states of the quantum circuits and the compensation signal is designed such that one of the hybridized states has an energy equal to an energy that one of the bare superposition state spanned by the quantum circuits would have in absence of cross-talk between the quantum circuits.
Claim CLM-00012. 12. A quantum processing device, comprising
at least two quantum circuits; a tunable coupler, to which the at least two quantum circuits are coupled, the circuits subject to cross-talk; and a control circuit, configured in the quantum processing device to apply: a primary signal to the quantum circuits so as to drive one or more energy transitions between states spanned by the quantum circuits; and a compensation signal designed so as to shift at least one state spanned by the quantum circuits, in energy, to compensate for cross-talk between the quantum circuits;
wherein the tunable coupler is designed such that a frequency thereof can be modulated so as to drive energy transitions in the quantum processing device and the control circuit is further configured in the quantum processing device to apply a synthesis signal to the tunable coupler, wherein the synthesis signal applied includes:
said primary signal, the latter modulated so as to modulate the frequency of the tunable coupler and thereby drive said one or more energy transitions via the tunable coupler, in operation; andsaid compensation signal, so as to compensate for cross-talk between the quantum circuits.
Claim CLM-00018. 18. A quantum processing chip, including
a plurality of cells, each comprising: at least two quantum circuits; and a tunable coupler, to which the at least two quantum circuits are coupled, the quantum circuits being subject to cross-talk,
wherein the quantum processing chip further comprises one or more further control circuits, configured in the chip to apply, for each of the cells:
a primary signal to respective quantum circuits so as to drive one or more energy transitions between states spanned by the respective quantum circuits via a respective tunable coupler, in operation; anda compensation signal designed so as to shift at least one state spanned by the respective quantum circuits, in energy, to compensate for cross-talk between two of said respective quantum circuits, in operation of the chip,wherein the tunable coupler is designed such that a frequency thereof can be modulated so as to drive energy transitions in the quantum processing chip and the control circuit is further configured in the quantum processing chip to apply a synthesis signal to the tunable coupler, wherein the synthesis signal applied includes:
said primary signal, the latter modulated so as to modulate the frequency of the tunable coupler and thereby drive said one or more energy transitions via the tunable coupler, in operation; andsaid compensation signal, so as to compensate for cross-talk between the quantum circuits.
