Fabrication of superconducting devices that control direct currents and microwave signals

A circuit, comprising:

• a direct current circuit that transmits a direct current comprising a first capacitor coupled to electrical ground and that shunts a first quarter-wavelength transmission line;
• a microwave circuit that transmits a microwave signal comprising a second capacitor coupled to electrical ground, wherein the second capacitor shunts a second quarter-wavelength transmission line, and wherein the microwave circuit comprises a third capacitor coupled to electrical ground;
• and
• a common circuit that transmits the direct current and the microwave signal and is coupled to a first end of the direct current circuit and to a first end of the microwave circuit.

A circuit comprising:

• a direct current circuit that transmits a direct current comprising a first capacitor coupled to electrical ground that shunts a first quarter-wavelength transmission line and a second capacitor coupled to electrical ground that shunts a second quarter-wavelength transmission line;
• a microwave circuit that transmits a microwave signal comprising a third capacitor coupled to electrical ground;
• and
• a common circuit that transmits the direct current and the microwave signal and is coupled to a first end of the direct current circuit and to a first end of the microwave circuit.

A circuit comprising:

• a first superconducting film deposited on a wafer comprising an inductor;
• a second superconducting film deposited on the first superconducting film;
• a dielectric film deposited on the second superconducting film;
• a third superconducting film deposited on the dielectric film;
• a direct current circuit that comprises a bandstop circuit that transmits a direct current;
• a microwave circuit that comprises a bandpass circuit that transmits a microwave signal;
• and
• a common circuit that transmits the direct current and the microwave signal, wherein a first end of the common circuit is coupled to a first end of the direct current circuit and to a first end of the microwave circuit;
• wherein the second superconducting film comprises the direct current circuit, the common circuit, and a first portion of the microwave circuit, and wherein the third superconducting film comprises a second portion of the microwave circuit.