Techniques are described herein that are capable of progressively thermally drying a quantum circuit. An inert gas is progressively heated by a heater element to provide a heated inert gas. Heated ambient air and the heated inert gas combine in a heating channel, causing a combination of the heated ambient air and the heated inert gas to flow into a probe compartment to progressively thermally dry a quantum circuit therein. A flow rate of the inert gas is controlled to cause the combination to have a relative humidity less than or equal to a threshold. A temperature of the heater element may be controlled to be approximately equal to a progressively increasing target temperature within a tolerance of 3.0° C. Heating of the inert gas may be initiated based on detection of the inert gas, and the flow and heating of the inert gas may be automatically discontinued.

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.

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 quantum computing device is formed using a first chip and a second chip, the first chip having a first substrate, a first set of pads, and a set of Josephson junctions disposed on the first substrate. The second chip has a second substrate, a second set of pads disposed on the second substrate opposite the first set of pads, and a second layer formed on a subset of the second set of pads. The second layer is configured to bond the first chip and the second chip. The subset of the second set of pads corresponds to a subset of the set of Josephson junctions selected to avoid frequency collision between qubits in a set of qubits. A qubit is formed using a Josephson junction from the subset of Josephson junctions and another Josephson junction not in the subset being rendered unusable for forming qubits.

Systems and techniques providing suitable chip structures for facilitating antenna-based thermal annealing of qubits are provided. In one example, a radio frequency emitter can comprise a voltage-controlled oscillator and an antenna. The voltage-controlled oscillator can receive power-on signals from a microcontroller, thereby causing the voltage-controlled oscillator to generate an electromagnetic wave. The antenna can then direct the electromagnetic wave onto a set of one or more capacitor pads of a Josephson junction on a superconducting qubit chip, thereby annealing the Josephson junction. In another example, a voltage regulator and a digital-to-analog converter or digital-to-digital converter can be coupled in series between the microcontroller and the voltage-controlled oscillator, thereby allowing the voltage-controlled oscillator to be voltage and/or frequency tunable and eliminating the need for external power routing as compared to photonic laser annealing. In yet another example, a bipolar-junction and complementary metal-oxide semiconductor stack construction can be employed.

A method for manufacturing a nanowire includes providing a sacrificial substrate, providing a patterned mask layer on the sacrificial substrate, providing a nanowire on the sacrificial substrate through an opening in the patterned mask layer, and removing the sacrificial substrate. Because the sacrificial substrate is used for growing the nanowire and later removed, the material of the sacrificial substrate can be chosen to be lattice matched with the material of the nanowire without regard to the electrical properties thereof. Accordingly, a high-quality nanowire can be grown and operated without the degradation in performance normally experienced when using a lattice matched substrate.

An electronic component (10) is formed by a semiconductor component or a semiconductor-like structure having gate electrode assemblies (16, 18), for reading out the quantum state of a qubit in a quantum dot (42). The electronic component (10) comprises a substrate (12) having a two-dimensional electron gas or electron hole gas. Electrical contacts connect the gate electrode assemblies (16, 18) to voltage sources. The gate electrode assemblies (16, 18) have gate electrodes (20, 22, 30, 32, 34, 38, 40), which are arranged on a surface (14) of the electronic component (10), for producing potential wells (46, 48, 62, 64, 66) in the substrate (12).

A superconducting circuit and a quantum computer capable of implementing four-body interaction using a plurality of superconducting qubit circuits supplied with signals of the same frequency are provided. A superconducting circuit (1) includes four superconducting qubit circuits (10), a coupling circuit (20) directly connected to the four superconducting qubit circuits (10). Each of the superconducting qubit circuits (10) indicates a qubit by being in a first phase state or a second phase state, when the number of the superconducting qubit circuits (10) in the first phase state among the four superconducting qubit circuits (10) is an even number, an interaction term of Hamiltonian of the superconducting circuit (1) takes a first value, and when the number of the superconducting qubit circuits (10) in the first phase state among the four superconducting qubit circuits (10) is an odd number, the interaction term takes a second value.

A superconducting quantum circuit includes a plurality of SQUIDs (Superconducting Quantum Interference Devices) connected in parallel, each of the plurality of SQUIDs including a first superconducting line, a first Josephson junction, a second superconducting line, and a second Josephson junction connected in a loop, wherein a junction area of the first Josephson junction and a junction area of the second Josephson junction are different from each other, the plurality of SQUIDs configured to be mutually different in either one or both of: a sum of the junction area of the first Josephson junction and the junction area of the second Josephson junction; and a ratio of the junction area of the first Josephson junction to the junction area of the second Josephson junction.