Abstract: Techniques facilitating low thermal conductivity support systems within cryogenic environments are provided. In one example, a cryostat can comprise a support rod and a washer. The support rod can couple first and second thermal stages of the cryostat. The washer can intervene between the support rod and the first thermal stage. The washer can thermally isolate the support rod and the first thermal stage.

Abstract: Devices and methods that facilitate modular quantum systems with discreet levels of connectivity are provided. In various embodiments, a quantum computing device can comprise one or more modules comprising at least qubits, buses, and readout structures; a plurality of couplers, wherein the plurality of couplers comprises at least two couplers selected from a group consisting of: classical couplers, short-range couplers, and long-range couplers, that are adapted for coupling a plurality of the at least qubits, buses, and readout structures; and a connection from the one or more modules to one or more classical controllers external to a cryogenic environment comprising the one or more modules.

Abstract: Techniques facilitating multiple cryogenic systems sectioned within a common vacuum space are provided. In one example, a cryostat can comprise a plurality of thermal stages and a thermal switch. The plurality of thermal stages can intervene between a 4-Kelvin (K) stage and a Cold Plate stage. The plurality of thermal stages can include a Still stage and an intermediate thermal stage that can be directly coupled mechanically to the Still stage via a support rod. The thermal switch can be coupled to the intermediate thermal stage and an adjacent thermal stage. The thermal switch can facilitate modifying a thermal profile of the cryostat by providing a switchable thermal path between the intermediate thermal stage and the adjacent thermal stage.

Abstract: Techniques for facilitating reduced thermal resistance attenuator on high-thermal conductivity substrates for quantum applications are provided. A device can comprise a substrate that provides a thermal conductivity level that is more than a defined thermal conductivity level. The device can also comprise one or more grooved transmission lines formed in the substrate. The one or more grooved transmission lines can comprise a powder substance. Further, the device can comprise one or more copper heat sinks formed in the substrate. The one or more copper heat sinks can provide a ground connection. Further, the one or more copper heat sinks can be formed adjacent to the one or more grooved transmission lines.

Abstract: Techniques facilitating efficient thermal profile management within cryogenic environments are provided. In one example, a cryostat can comprise a plurality of thermal stages intervening between a 4-Kelvin (K) stage and a Cold Plate stage. The plurality of thermal stages can include a Still stage and an intermediate thermal stage that provides additional cooling capacity for the cryostat. The intermediate thermal stage can be directly coupled mechanically to the Still stage via a support rod.

Abstract: A method for adjusting a resonance frequency of a qubit in a quantum mechanical device includes providing a substrate having a frontside and a backside, the frontside having at least one qubit formed thereon, the at least one qubit comprising capacitor pads; and removing substrate material from the backside of the substrate at an area opposite the at least one qubit to alter a capacitance around the at least one qubit so as to adjust a resonance frequency of the at least one qubit.

Abstract: Techniques facilitating mechanical vibration management for cryogenic environments are provided. In one example, a system can comprise a processor that executes computer executable components stored in memory. The computer executable components can comprise a linearization component and a drive component. The linearization component can translate data indicative of a nonlinear drive signal into a linear drive signal. The drive component can dynamically control operation of a compressor of a cryocooler using the linear drive signal. The cryocooler can provide cooling capacity for a cryogenic environment.

Abstract: A quantum circuit includes a quantum signal unit. There is a first quantum chip comprising a plurality of qubit devices and bi-directionally coupled to the quantum signal unit. A first quantum entangling unit is bi-directionally coupled to the quantum signal unit and configured to generate an entanglement between a first and a second qubit device on the first quantum chip via the quantum signal unit.

Abstract: A stripline that is usable in a quantum application (q-stripline) includes a first polyimide film and a second polyimide film. The q-stripline further includes a first center conductor and a second center conductor formed between the first polyimide film and the second polyimide film. The q-stripline has a first pin configured through the second polyimide film to make electrical and thermal contact with the first center conductor.

Abstract: A microstrip that is usable in a quantum application (q-microstrip) includes a ground plane, a polyimide film disposed over the ground plane at a first surface of the polyimide film, and a conductor formed on a second side of the polyimide film such that the first surface is substantially opposite to the second surface. A material of the conductor provides greater than a threshold thermal conductivity (TH) with a structure of a dilution fridge stage (stage).

Abstract: Techniques for forming quantum circuits, including connections between components of quantum circuits, are presented. A trench can be formed in a dielectric material, by removing a portion of the dielectric material and a portion of conductive material layered on top of the dielectric material, to enable creation of circuit components of a circuit. The trench can define a regular nub or compensated nub to facilitate creating electrical leads connected to the circuit components on a nub. The compensated nub can comprise recessed regions to facilitate depositing material during evaporation to form the leads. For compensated nub implementation, material can be evaporated in two directions, with oxidation performed in between such evaporations, to contact leads and form a Josephson junction. For regular nub implementation, material can be evaporated in four directions, with oxidation performed in between the third and fourth evaporations, to contact leads and form a Josephson junction.

Abstract: Techniques for facilitating reduced thermal resistance attenuator on high-thermal conductivity substrates for quantum applications are provided. A device can comprise a substrate that provides a thermal conductivity level that is more than a defined thermal conductivity level. The device can also comprise one or more grooved transmission lines formed in the substrate. The one or more grooved transmission lines can comprise a powder substance. Further, the device can comprise one or more copper heat sinks formed in the substrate. The one or more copper heat sinks can provide a ground connection. Further, the one or more copper heat sinks can be formed adjacent to the one or more grooved transmission lines.

Abstract: A method for adjusting a resonance frequency of a qubit in a quantum mechanical device includes providing a substrate having a frontside and a backside, the frontside having at least one qubit formed thereon, the at least one qubit comprising capacitor pads; and removing substrate material from the backside of the substrate at an area opposite the at least one qubit to alter a capacitance around the at least one qubit so as to adjust a resonance frequency of the at least one qubit.

Abstract: 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.

Abstract: A signal generating system is provided. The signal generating system provides a microwave signal to a plurality of qubits. The signal generating system includes a generator, an oscillator, a mixer, and a splitter. The oscillator generates an oscillator signal including a constant frequency. The generator generates a generator signal including an initial frequency. The mixer is electrically coupled to the generator and the oscillator. The mixer combines the generator and oscillator signals to produce the microwave signal. The splitter is electrically coupled to the mixer. The splitter fans-out the microwave signal to a plurality of physical lines. Each of the plurality of physical lines is electrically connected to a corresponding one of the plurality of qubits.

Abstract: 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.

Abstract: 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.

Abstract: Techniques for facilitating reduced thermal resistance attenuator on high-thermal conductivity substrates for quantum applications are provided. A device can comprise a substrate that provides a thermal conductivity level that is more than a defined thermal conductivity level. The device can also comprise one or more grooved transmission lines formed in the substrate. The one or more grooved transmission lines can comprise a powder substance. Further, the device can comprise one or more copper heat sinks formed in the substrate. The one or more copper heat sinks can provide a ground connection. Further, the one or more copper heat sinks can be formed adjacent to the one or more grooved transmission lines.

Abstract: Techniques facilitating low thermal conductivity support systems within cryogenic environments are provided. In one example, a cryostat can comprise a support rod and a washer. The support rod can couple first and second thermal stages of the cryostat. The washer can intervene between the support rod and the first thermal stage. The washer can thermally isolate the support rod and the first thermal stage.

Abstract: Techniques facilitating efficient thermal profile management within cryogenic environments are provided. In one example, a cryostat can comprise a plurality of thermal stages intervening between a 4-Kelvin (K) stage and a Cold Plate stage. The plurality of thermal stages can include a Still stage and an intermediate thermal stage that provides additional cooling capacity for the cryostat. The intermediate thermal stage can be directly coupled mechanically to the Still stage via a support rod.