Qubit tuning by magnetic fields in superconductors

A computer usable program product for tuning a qubit, the computer program product comprising a computer-readable storage device, and program instructions stored on the storage device, the stored program instructions comprising:

• program instructions to generate a first magnetic field through a portion of a first layer, the first layer comprising a material exhibiting superconductivity in a cryogenic temperature range, the portion of the first layer above a critical temperature;
• program instructions to cool the portion of the first layer at least to the critical temperature;
• and
• program instructions to generate, in response to cooling the portion of the first layer at least to the critical temperature, a second magnetic field to magnetically interact with a qubit of a quantum processor chip such that a first magnetic flux of the first layer causes a first change in a first resonance frequency of the qubit by a first frequency shift value.

A computer system for tuning a qubit, the computer system comprising a processor, a computer-readable memory, and a computer-readable storage device, and program instructions stored on the storage device for execution by the processor via the memory, the stored program instructions comprising:

• program instructions to generate a first magnetic field through a portion of a first layer, the first layer comprising a material exhibiting superconductivity in a cryogenic temperature range, the portion of the first layer above a critical temperature;
• program instructions to cool the portion of the first layer at least to the critical temperature;
• and
• program instructions to generate, in response to cooling the portion of the first layer at least to the critical temperature, a second magnetic field to magnetically interact with a qubit of a quantum processor chip such that a first magnetic flux of the first layer causes a first change in a first resonance frequency of the qubit by a first frequency shift value.