Abstract: A circuit configured to transmit frequency multiplexed signals from a superconducting domain to a higher temperature domain. The circuit comprising a multiplexed signal output and a plurality of superconducting oscillator circuits each configured to output a different carrier frequency, each superconducting oscillator circuit comprising an oscillator output connected to the multiplexed signal output. Each superconducting oscillator circuit comprising a converter stage configured to convert an input of a superconducting logic signal to a Single Flux Quantum (SFQ) bit value, a splitter stage electrically connected to an output of the converter stage, the splitter stage configured to change between a first current state and a second current state based at least in part on the SFQ bit value, and an oscillator stage magnetically coupled to an output of the splitter stage and electrically coupled to the oscillator output.

Abstract: Examples described in this disclosure relate to sub-kelvin control systems and methods for scalable quantum control. An example system includes a first cooling sub-system operable to maintain an operating temperature for a first device within a first sub-kelvin temperature range. The system further includes a second cooling sub-system, separate from the first cooling sub-system, operable to maintain an operating temperature for a second device, different from the first device, within a second sub-kelvin temperature range. The first sub-kelvin range may comprise a range between 50 milli-kelvin (mK) to 999 mK and the second sub-kelvin range may comprise a range between 1 mK to 299 mK. The combination of the first cooling sub-system and the second cooling sub-system is configured to maintain a temperature gradient between the first device and the second device despite the first device and the second device being in close proximity to each other.

Abstract: A circuit configured to transmit frequency multiplexed signals from a superconducting domain to a higher temperature domain. The circuit comprising a multiplexed signal output and a plurality of superconducting oscillator circuits each configured to output a different carrier frequency, each superconducting oscillator circuit comprising an oscillator output connected to the multiplexed signal output. Each superconducting oscillator circuit comprising a converter stage configured to convert an input of a superconducting logic signal to a Single Flux Quantum (SFQ) bit value, a splitter stage electrically connected to an output of the converter stage, the splitter stage configured to change between a first current state and a second current state based at least in part on the SFQ bit value, and an oscillator stage magnetically coupled to an output of the splitter stage and electrically coupled to the oscillator output.