An apparatus includes an isolation barrier configured to absorb electromagnetic energy. The isolation barrier includes multiple layers stacked on one another. Each of the multiple layers includes at least one dielectric material, at least one thin-film resistive material carried by the at least one dielectric material, and conductive strips in electrical contact with the at least one thin-film resistive material. The isolation barrier also includes vias through the multiple layers. Multiple ones of the vias are positioned along each of the conductive strips, and the vias electrically couple the conductive strips in the multiple layers to one another. The isolation barrier is configured to guide the electromagnetic energy through the multiple layers to enable absorption of the electromagnetic energy by the at least one thin-film resistive material.

An apparatus includes an isolation barrier configured to absorb electromagnetic energy. The isolation barrier includes multiple layers stacked on one another. Each of the multiple layers includes at least one dielectric material, at least one thin-film resistive material carried by the at least one dielectric material, and conductive strips in electrical contact with the at least one thin-film resistive material. The isolation barrier also includes vias through the multiple layers. Multiple ones of the vias are positioned along each of the conductive strips, and the vias electrically couple the conductive strips in the multiple layers to one another. The isolation barrier is configured to guide the electromagnetic energy through the multiple layers to enable absorption of the electromagnetic energy by the at least one thin-film resistive material.

A Wilkinson power combiner (202) is described that includes: at least one input port (210) coupled to at least one output port (212, 214, 216, 218) by at least two power combining stages. A first power combining stage (204) of the at least two power combining stages is configured as a single-stage first frequency pass circuit and a second power combining stage (206) of the at least two stages is configured as a single-stage second frequency pass circuit, and wherein the first frequency is different to the second frequency.

A Wilkinson power combiner (202) is described that includes: at least one input port (210) coupled to at least one output port (212, 214, 216, 218) by at least two power combining stages. A first power combining stage (204) of the at least two power combining stages is configured as a single-stage first frequency pass circuit and a second power combining stage (206) of the at least two stages is configured as a single-stage second frequency pass circuit, and wherein the first frequency is different to the second frequency.

A non-reciprocal microwave network is provided that includes an in-line ferromagnetic element with adjoining polarizing adapters to achieve directivity via a multi-mode interaction at or near the ferrite to act as new class of 4-port circulator or 2-port isolator, with standard waveguide inputs for assembly in larger networks.

Fabrication of superconducting devices that combine or separate direct currents and microwave signals is provided. A method can comprise forming a direct current circuit that supports a direct current, a microwave circuit that supports a microwave signal, and a common circuit that supports the direct current and the microwave signal. The method can also comprise operatively coupling a first end of the direct current circuit and a first end of the microwave circuit to a first end of the common circuit. The direct current circuit can comprise a bandstop circuit and the microwave circuit can comprise a capacitor. Alternatively, the direct current circuit can comprise a bandstop circuit and the microwave circuit can comprise a bandpass circuit. Alternatively, the microwave circuit can comprise a capacitor and the direct current circuit can comprise one or more quarter-wavelength transmission lines.

A non-reciprocal microwave network is provided that includes an in-line ferromagnetic element with adjoining polarizing adapters to achieve directivity via a multi-mode interaction at or near the ferrite to act as new class of 4-port circulator or 2-port isolator, with standard waveguide inputs for assembly in larger networks.

A Wilkinson power combiner (202) is described that includes: at least one input port (210) coupled to at least one output port (212, 214, 216, 218) by at least two power combining stages. A first power combining stage (204) of the at least two power combining stages is configured as a single-stage first frequency pass circuit and a second power combining stage (206) of the at least two stages is configured as a single-stage second frequency pass circuit, and wherein the first frequency is different to the second frequency.

A Wilkinson power combiner (202) is described that includes: at least one input port (210) coupled to at least one output port (212, 214, 216, 218) by at least two power combining stages. A first power combining stage (204) of the at least two power combining stages is configured as a single-stage first frequency pass circuit and a second power combining stage (206) of the at least two stages is configured as a single-stage second frequency pass circuit, and wherein the first frequency is different to the second frequency.

A device for unidirectional propagation of microwaves comprises a resonant microwave structure arranged to transmit microwaves between two ports and a magnetic source arranged to provide a generally static magnetic field and to have a resonant frequency distinct from that of the microwave structure, which is disposed adjacent the microwave structure so as to be located in presence of electromagnetic fields emanating from the transmitted microwaves such that the magnetic field interacts with the electromagnetic fields of the microwaves so as to form a set of hybridized resonant frequencies at which zero intrinsic damping exists, one of the set of hybridized resonant frequencies being a real eigenvalue providing the unidirectional propagation from one of the first and second ports to the other. A related method comprises arranging the magnetic source at a prescribed position where the real eigenvalue matches the frequency of an input signal applied at a selected port.