Thermalization of microwave attenuators for quantum computing signal lines

A device, comprising:

• a housing component that contains a microwave signal attenuator chip, the housing component comprising a metal having a thermal conductivity of about at least 1 Watts per meter-Kelvin at 1 degree Kelvin, wherein the thermal conductivity is selected to facilitate functionality of a quantum processor;
• a first subassembly that is mechanically coupled to the housing component, the first subassembly comprising a first microwave connector having a first microwave signal conductor electrically coupled to an input side of the microwave signal attenuator chip, wherein the microwave signal attenuator chip is outside of the housing component, wherein the first microwave connector is directly connected to a coax coupling portion disposed to directly connect to the housing component via the coax coupling portion adapted to directly attach to the housing component, and wherein the first microwave signal conductor is directly connected to and provided via the coax coupling portion;
• and
• a second subassembly that is mechanically coupled to the housing component, the second subassembly comprising a second microwave connector having a second microwave signal conductor electrically coupled to an output side of the microwave signal attenuator chip.

A device, comprising:

• an input microwave connector component comprising an input signal conductor, the input signal conductor electrically coupled to an input of a microwave signal attenuator chip;
• an output microwave connector component comprising an output signal conductor, the output signal conductor electrically coupled to an output of the microwave signal attenuator chip;
• and
• a housing component, the housing component having a first thermal conductivity of about at least 0.1 Watts per meter-Kelvin at 1 degree Kelvin, the housing component affixed to the microwave signal attenuator chip with a fastening material having a second thermal conductivity of about at least 0.1 Watts per meter-Kelvin at 1 degree Kelvin, and the housing component directly mechanically connected to the input microwave connector component via a coax coupling portion formed to be received in a recess of the housing component, and to the output microwave connector component, wherein the first thermal conductivity are the second thermal conductivity are selected to facilitate functionality of a quantum processor.

A cryogenic microwave attenuator device, comprising:

• a housing component having a thermal conductivity of about at least 0.1 Watts per meter-Kelvin at 1 degree Kelvin, the housing component coupled to dissipate thermal energy of a microwave signal attenuator chip contained within the housing component, wherein the thermal conductivity is selected to facilitate functionality of a quantum processor;
• an input microwave connector component mechanically coupled to the housing component, the input microwave connector component comprising an input signal conductor, the input signal conductor direct wire bonded to an input of the microwave signal attenuator chip wherein the input microwave connector is directly connected to a coax coupling portion disposed to directly connect to the housing component via the coax coupling portion adapted to directly attach to the housing component, and wherein the input signal conductor is directly connected to and provided via the coax coupling portion;
• and
• an output microwave connector component mechanically coupled to the housing component, the output microwave connector component comprising an output signal conductor, the output signal conductor direct wire bonded to an output of the microwave signal attenuator chip.

A method, comprising:

• constructing a package assembly for a microwave signal attenuator device, comprising,
• affixing a microwave signal attenuator chip to a housing component, the housing component having a thermal conductivity of about at least 0.1 Watts per meter-Kelvin at 1 degree Kelvin, wherein the thermal conductivity is selected to facilitate functionality of a quantum processor;
• coupling a first microwave connector subassembly to the housing component;
• coupling a second microwave connector subassembly to the housing component, wherein the first microwave connector subassembly comprises:
• a first microwave connector directly connected to a coax coupling portion disposed to directly connect to the housing component via the coax coupling portion;
• and
• a first microwave signal conductor directly connected to and provided via the coax coupling portion and disposed to slide onto a recess of the housing component;
• wire bonding an input side of the microwave signal attenuator chip to a first microwave connector signal conductor;
• and
• wire bonding an output side of the microwave signal attenuator chip to a second microwave connector signal conductor.