Abstract: A qubit interaction circuit includes a first qubit device, a second qubit device, a first resonator, a second resonator, a first capacitor coupling the first qubit device to the first resonator and a second capacitor coupling the second qubit device to the second resonator. An rf-SQUID circuit includes an rf-SQUID loop, an rf-SQUID controller, and a dc-SQUID loop. The rf-SQUID controller is configured to influence a first flux of the rf-SQUID loop and the dc-SQUID loop, the rf-SQUID circuit coupling the first resonator with the second resonator. A dc-SQUID controller is configured to influence a second flux of the rf-SQUID loop and the dc-SQUID loop.

Abstract: A device comprises a first superconducting quantum bit, a second superconducting quantum bit, and a coupler circuit. The first superconducting quantum bit comprises a superconducting tunnel junction and a shunt inductor which form a first superconducting loop. The second superconducting quantum bit comprises a superconducting tunnel junction and a shunt inductor which form a second superconducting loop. The coupler circuit is coupled between the first and second superconducting quantum bits. The coupler circuit is configured to implement an entanglement gate operation between the first and second superconducting quantum bits through exchange interactions between the coupler circuit and the first superconducting quantum bit and the second superconducting quantum bit, when the coupler circuit is driven by a control signal.

Abstract: Techniques are provided for mediating interactions (e.g., long range interactions) between quantum bits to facilitate quantum computing operations such as two-qubit gate operations. A device comprises a first quantum bit, a second quantum bit, and a coupling bus connecting the first quantum bit and the second quantum bit. The coupling bus comprises a plurality of transmission line resonators which are coupled in series, and at least one tunable inductive coupler to control a coupling between a first transmission line resonator and a second transmission line resonator of the plurality of transmission line resonators.

Abstract: A device comprises a data quantum bit, a first quantum bit coupler, a second quantum bit coupler, and an auxiliary quantum bit. The first quantum bit coupler is coupled to the data quantum bit. The second quantum bit coupler is coupled to the first quantum bit coupler. The auxiliary quantum bit is coupled to the second quantum bit coupler. The first quantum bit coupler is configured to operate in a state to suppress interaction between the data quantum bit and the auxiliary quantum bit. The first quantum bit coupler and the second quantum bit coupler are each configured to operate in a respective state to enable interaction between the data quantum bit and the auxiliary quantum bit and entangle a state of the data quantum bit with a state of the auxiliary quantum bit.

Abstract: A device comprises first and second superconducting quantum bits, and a multimode coupler circuit coupled between the first and second superconducting quantum bits. The multimode coupler circuit comprises a first mode and a second mode, and is configured to operate in one of a first state and a second state, in response to a flux tuning control signal. In the first state, the first superconducting quantum bit is exchange coupled to the first mode, and the second superconducting quantum bit is exchange coupled to the second mode, to suppress interaction between the first and second superconducting quantum bits. In the second state, the first and second superconducting quantum bits are exchange coupled to both the first and second modes, to enable an interaction between the first and second superconducting quantum bits and perform an entanglement gate operation.

Abstract: Techniques are provided for mediating interactions (e.g., long range interactions) between quantum bits to facilitate quantum computing operations such as two-qubit gate operations. A device comprises a first quantum bit, a second quantum bit, and a coupling bus connecting the first quantum bit and the second quantum bit. The coupling bus comprises a plurality of transmission line resonators which are coupled in series, and at least one tunable inductive coupler to control a coupling between a first transmission line resonator and a second transmission line resonator of the plurality of transmission line resonators.

Abstract: Techniques and couplers for managing coupling between qubits are presented. A first tuneable coupler qubit (TCQ) can comprise a first frequency mode and a second frequency mode. A second TCQ can comprise a third frequency mode and a fourth frequency mode. First TCQ can be selectively coupled to a first qubit based on the first frequency mode and selectively coupled to the second TCQ based on the second and third frequency modes. Second TCQ can be selectively coupled to a second qubit based on the fourth frequency mode. When certain respective magnetic fluxes are applied to first and second TCQs, ZZ interaction between the first and second qubits can be suppressed. When respective modified magnetic fluxes are applied to first and second TCQs to excite respective frequency modes, coupling can occur, and ZZ interaction and an entangled gate can be created between the first and second qubits.

Abstract: One or more electronic systems, electronic structures and/or methods provided herein relate to quantum state measurement while suppressing measurement-induced state transition in a superconducting qubit. An electronic system can comprise a superconducting qubit coupled to a tunable coupler qubit (TCQ), and a microwave drive port coupled to the TCQ. A resonator can be coupled between the TCQ and the microwave drive port. The resonator can be coupled to the microwave drive port by direct capacitive coupling or inductive coupling. The superconducting qubit can be coupled to the TCQ by a pair of parallelly-arranged coupling capacitors having equal capacitance to one another, or the resonator can be coupled to the TCQ by a pair of parallelly-arranged coupling capacitors having equal capacitance to one another.

Abstract: A qubit interaction circuit includes a first qubit device, a second qubit device, a first resonator, a second resonator, a first capacitor coupling the first qubit device to the first resonator and a second capacitor coupling the second qubit device to the second resonator. An rf-SQUID circuit includes an rf-SQUID loop, an rf-SQUID controller, and a dc-SQUID loop. The rf-SQUID controller is configured to influence a first flux of the rf-SQUID loop and the dc-SQUID loop, the rf-SQUID circuit coupling the first resonator with the second resonator. A dc-SQUID controller is configured to influence a second flux of the rf-SQUID loop and the dc-SQUID loop.

Abstract: A package structure comprises a first quantum bit chip and a second quantum bit chip mounted on a carrier substrate. The carrier substrate comprises an inter-chip coupling network which is configured to provide non-galvanic and differential coupling of the first quantum bit chip and the second quantum bit chip.

Abstract: Devices and/or computer-implemented methods facilitating suppression of spectator effects between qubits are provided. In an embodiment, a device can comprise a tunable-coupler qubit (TCQ), wherein a middle pad of the TCQ is coupled to a first capacitively-shunted flux qubit (CSFQ) coupler and wherein outer pads of the TCQ are coupled to a second CSFQ coupler; a first superconducting qubit coupled to the first CSFQ coupler; and a second superconducting qubit coupled to the second CSFQ coupler.

Abstract: Devices and/or computer-implemented methods facilitating suppression of cross-talk between qubits are provided. In an embodiment, a device can comprise a first transmon qubit coupled to a first tunable coupled qubit (TCQ) interconnect, wherein each pad of the first transmon qubit are coupled to corresponding outer pads of the first TCQ interconnect; a second transmon qubit coupled to a second TCQ interconnect, wherein each pad of the second transmon qubit are coupled to corresponding outer pads of the second TCQ interconnect; and a middle pad of the first TCQ interconnect coupled to a middle pad of the second TCQ interconnect, wherein the coupling comprises each middle pad coupled to a resonator.

Abstract: Various systems and methods are presented regarding utilizing a spiral resonator to enhance coupling between a first inductor loop and a second inductor loop to enable coupling between a first qubit and a second qubit. Operation of the first inductor loop can be controlled by a flux-tunable TCQ coupler, wherein flux-tuning can adjust operation from an OFF state (no coupling between the first qubit and the second qubit) to an ON state (the first qubit and second qubit are coupled). The spiral resonator can be located at the center of, and in the same plane as the loop of the first inductor loop. The spiral resonator can enhance inductive coupling between the first loop inductor and the second loop inductor.

Abstract: One or more electronic systems, electronic structures and/or methods provided herein relate to quantum state measurement while suppressing measurement-induced state transition in a superconducting qubit. An electronic system can comprise a superconducting qubit coupled to a tunable coupler qubit (TCQ), and a microwave drive port coupled to the TCQ. A resonator can be coupled between the TCQ and the microwave drive port. The resonator can be coupled to the microwave drive port by direct capacitive coupling or inductive coupling. The superconducting qubit can be coupled to the TCQ by a pair of parallelly-arranged coupling capacitors having equal capacitance to one another, or the resonator can be coupled to the TCQ by a pair of parallelly-arranged coupling capacitors having equal capacitance to one another.

Abstract: Devices and/or computer-implemented methods to facilitate ZZ cancellation between qubits are provided. According to an embodiment, a device can comprise a coupler device that operates in a first oscillating mode and a second oscillating mode. The device can further comprise a first superconducting qubit coupled to the coupler device based on a first oscillating mode structure corresponding to the first oscillating mode and based on a second oscillating mode structure corresponding to the second oscillating mode. The device can further comprise a second superconducting qubit coupled to the coupler device based on the first oscillating mode structure and the second oscillating mode structure.

Abstract: Systems and techniques that facilitate mode-selective couplers for frequency collision reduction are provided. In various embodiments, a device can comprise a control qubit. In various aspects, the device can comprise a first target qubit coupled to the control qubit by a first mode-selective coupler. In various instances, the first mode-selective coupler can facilitate A-mode coupling between the control qubit and the first target qubit. In various embodiments, the device can comprise a second target qubit coupled to the control qubit by a second mode-selective coupler. In various aspects, the second mode selective coupler can facilitate B-mode coupling between the control qubit and the second target qubit. In various embodiments, the first mode-selective coupler can comprise a capacitor that capacitively couples a middle capacitor pad of the control qubit to a middle capacitor pad of the first target qubit.

Abstract: Devices and/or computer-implemented methods facilitating static ZZ suppression and Purcell loss reduction using mode-selective coupling in two-junction superconducting qubits are provided. In an embodiment, a device can comprise a superconducting bus resonator. The device can further comprise a first superconducting qubit. The device can further comprise a second superconducting qubit, the first superconducting qubit and the second superconducting qubit respectively comprising: a first superconducting pad; a second superconducting pad; a third superconducting pad; a first Josephson Junction coupled to the first superconducting pad and the second superconducting pad; and a second Josephson Junction coupled to the second superconducting pad and the third superconducting pad. The first superconducting pad and the second superconducting pad of the first superconducting qubit and the second superconducting qubit are coupled to the superconducting bus resonator.

Abstract: Devices and/or computer-implemented methods to facilitate ZZ cancellation between qubits are provided. According to an embodiment, a device can comprise a coupler device that operates in a first oscillating mode and a second oscillating mode. The device can further comprise a first superconducting qubit coupled to the coupler device based on a first oscillating mode structure corresponding to the first oscillating mode and based on a second oscillating mode structure corresponding to the second oscillating mode. The device can further comprise a second superconducting qubit coupled to the coupler device based on the first oscillating mode structure and the second oscillating mode structure.

Abstract: An electronic structure can include a first superconducting quantum interference device (SQUID) coupled between a first pad and a second pad of a first tunable coupler qubit (TCQ) having a first qubit, and a first Josephson Junction (JJ) coupled between a second pad and a third pad of the first TCQ. The electronic structure can include a second SQUID coupled between a first pad and a second pad of a second TCQ having a second qubit, and a second JJ coupled between the second pad and a third pad of the second TCQ. The second pad of the first TCQ can be coupled to the second pad of the second TCQ. The first TCQ can be coupled to a first driveline, and the second TCQ can be coupled to a second driveline.

Abstract: Systems and techniques that facilitate mitigating stray-coupling via multi junction qubits are provided. In various embodiments, a device can comprise a first qubit having a plurality of Josephson junctions respectively between a plurality of capacitor pads. In various aspects, the device can further comprise a plurality of second qubits respectively coupled to different ones of the plurality of capacitor pads, such that no two of the plurality of second qubits can be coupled to a same one of the plurality of capacitor pads.