An embodiment of a qubit tuning device includes a first layer configured to generate a magnetic field, the first layer comprising a material exhibiting superconductivity in a cryogenic temperature range. In an embodiment, the qubit tuning device includes a qubit of a quantum processor chip, wherein the first layer is configured to magnetically interact with the qubit 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 device including: a semiconductor layer comprising first regions delimited by second regions and third regions; first electrostatic control gates including first conductive portions extending parallel to each other, in vertical alignment with the second regions; second electrostatic control gates including second conductive portions extending parallel to each other, in vertical alignment with the third regions;
wherein each first gate includes an electrostatic control voltage adjustment element forming two impedances connected in series, one end of one of the impedances being coupled to the first conductive portion of the first gate and one end of the other of the impedances being coupled to a third conductive portion applying an adjustment electric potential to the second impedance, and wherein the value of at least one of the impedances is adjustable.

Superconducting through substrate vias (STSVs) are disclosed. The STSVs provide superconducting interconnections between opposite faces of a substrate. In an example, a method of forming STSVs includes etching openings that extend from a first side of a substrate partially through the substrate towards a second side of the substrate. The method also includes depositing a seed layer over the first side of the substrate and interior surfaces of the openings in the substrate. The method further includes forming a resist or hardmask on the first side of the substrate above the seed layer, such that the resist or hardmask comprises openings aligned with the etched openings in the substrate. The etched openings in the substrate are filled with a superconducting filler material. The substrate is thinned by removing material from the second side of the substrate until the deposited seed layer is exposed on the second side of the substrate.

The invention relates to a method for forming flip chip bumps using electroplating. The method allows the formation of flip chip bumps in a way that is compatible with already-formed sensitive electronic components, such as Josephson junctions, which may be used in quantum processing units. The invention also relates to a product and a flip chip package in which flip chip bumps are formed with the disclosed method.

Quantum computing assemblies, and related devices and methods, are disclosed herein. For example, in some embodiments, a quantum computing assembly may include: a package substrate; a first die coupled to the package substrate; and a second die coupled to the second surface of the package substrate and coupled to the first die; wherein the first die or the second die includes quantum processing circuitry.

A stacked device including a first substrate that includes a quantum information processing device, a second substrate bonded to the first substrate, and multiple bump bonds and at least one pillar between the first substrate and the second substrate. Each bump bond of the multiple bump bonds provides an electrical connection between the first substrate and the second substrate. At least one pillar defines a separation distance between a first surface of the first substrate and a first surface of the second substrate. A cross-sectional area of each pillar is greater than a cross-sectional area of each bump bond of the multiple bump bonds, where the cross-sectional area of each pillar and of each bump bond is defined along a plane parallel to the first surface of the first substrate or to the first surface of the second substrate.

A quantum computing system that includes a quantum circuit device having at least one operating frequency; a first substrate having a first surface on which the quantum circuit device is disposed; a second substrate having a first surface that defines a recess of the second substrate, the first and second substrates being arranged such that the recess of the second substrate forms an enclosure that houses the quantum circuit device; and an electrically conducting layer that covers at least a portion of the recess of the second substrate.

Methods for mitigating microwave crosstalk and forming a component in a superconducting integrated circuit are discussed. Mitigating microwave crosstalk involves forming a microwave shield within the superconducting integrated circuit, the superconducting integrated circuit including a microwave sensitive component. The microwave shield is formed from a base layer and one or more sides, and the footprint of the microwave sensitive component is contained within the footprint of the microwave shielding base layer, with the one or more sides extending around at least a portion of the microwave sensitive component. Forming a component involves depositing a first metal layer, depositing a dielectric layer overlying the first metal layer, the dielectric layer comprising Nb.sub.2O.sub.5 that is deposited by atomic layer deposition, and depositing a second metal layer overlying the dielectric layer.

Methods for mitigating microwave crosstalk and forming a component in a superconducting integrated circuit are discussed. Mitigating microwave crosstalk involves forming a microwave shield within the superconducting integrated circuit, the superconducting integrated circuit including a microwave sensitive component. The microwave shield is formed from a base layer and one or more sides, and the footprint of the microwave sensitive component is contained within the footprint of the microwave shielding base layer, with the one or more sides extending around at least a portion of the microwave sensitive component. Forming a component involves depositing a first metal layer, depositing a dielectric layer overlying the first metal layer, the dielectric layer comprising Nb.sub.2O.sub.5 that is deposited by atomic layer deposition, and depositing a second metal layer overlying the dielectric layer.

An electronic or optoelectronic device includes: (1) a layer of a first material; and (2) a layer of a second material disposed on the layer of the first material, wherein the first material is different from the second material, and the layer of the first material is spaced from the layer of the second material by a gap.