An on-chip microwave filter circuit includes a substrate formed of a first material that exhibits at least a threshold level of thermal conductivity, wherein the threshold level of thermal conductivity is achieved at a cryogenic temperature range in which a quantum computing circuit operates. The filter circuit further includes a dispersive component configured to filter a plurality of frequencies in an input signal, the dispersive component including a first transmission line disposed on the substrate, the first transmission line being formed of a second material that exhibits at least a second threshold level of thermal conductivity, where the second threshold level of thermal conductivity is achieved at a cryogenic temperature range in which a quantum computing circuit operates. The dispersive component further includes a second transmission line disposed on the substrate, the second transmission line being formed of the second material.

A high speed circuit and a method for fabricating the same is disclosed. The high speed circuit has a printed circuit board. A pair of first and second differential traces are formed on a first surface of the printed circuit board. The differential traces carry an electrical signal. A partial loop extends through the printed circuit board. The partial loop includes first and second end slots under the first and second differential traces. The partial loop includes a pair of side slots substantially parallel to the differential traces. An anchor member connects the printed circuit board to an island formed by the first and second end slots and side slots. The anchor member forms a gap in one of the end slots or side slots. The length of the side slots and the length of the gap is selected to reduce a target common mode frequency from the electrical signal.

An on-chip microwave filter circuit includes a substrate formed of a first material that exhibits at least a threshold level of thermal conductivity, wherein the threshold level of thermal conductivity is achieved at a cryogenic temperature range in which a quantum computing circuit operates. The filter circuit further includes a dispersive component configured to filter a plurality of frequencies in an input signal, the dispersive component including a first transmission line disposed on the substrate, the first transmission line being formed of a second material that exhibits at least a second threshold level of thermal conductivity, wherein the second threshold level of thermal conductivity is achieved at a cryogenic temperature range in which a quantum computing circuit operates. The dispersive component further includes a second transmission line disposed on the substrate, the second transmission line being formed of the second material.

A high speed circuit and a method for fabricating the same is disclosed. The high speed circuit has a printed circuit board. A pair of first and second differential traces are formed on a first surface of the printed circuit board. The differential traces carry an electrical signal. A partial loop extends through the printed circuit board. The partial loop includes first and second end slots under the first and second differential traces. The partial loop includes a pair of side slots substantially parallel to the differential traces. An anchor member connects the printed circuit board to an island formed by the first and second end slots and side slots. The anchor member forms a gap in one of the end slots or side slots. The length of the side slots and the length of the gap is selected to reduce a target common mode frequency from the electrical signal.

An example system includes a communication channel and at least one tuning structure coupled to the communication channel. The tuning structure includes a branch of the communication channel. The tuning structure is to dissipate energy from the communication channel at least at one selected wavelength. The branch of the communication channel is a terminated portion.

The present invention includes a method for creating a system in a package with integrated lumped element devices is system-in-package (SiP) or in photo-definable glass, comprising: masking a design layout comprising one or more electrical components on or in a photosensitive glass substrate; activating the photosensitive glass substrate, heating and cooling to make the crystalline material to form a glass-crystalline substrate; etching the glass-crystalline substrate; and depositing, growing, or selectively etching a seed layer on a surface of the glass-crystalline substrate on the surface of the photodefinable glass, wherein the integrated lumped element devices reduces the parasitic noise and losses by at least 25% from a package lumped element device mount to a system-in-package (SiP) in or on photo-definable glass when compared to an equivalent surface mounted device.

A wide bandpass filtering power amplifier using discriminating coupling is disclosed, which comprises a DC bias circuit, an input impedance matching circuit, a transistor and an output impedance matching circuit. The DC bias circuit is connected to the input impedance matching circuit which is further connected to the transistor, and the transistor is further connected to the output impedance matching circuit which comprises a tuning microstrip line and a bandpass filter. The complexity and the area of the impedance matching circuit in the power amplifier are effectively reduced. At the same time, the filtering PA has good frequency selectivity by using the discriminating coupling BPF. Meanwhile the work efficiency and bandwidth of the filtering power amplifier are effectively improved by taking both of the extended continuous mode theory and filter synthesis theory into account.

A transmission-line-based impedance transformer including first and second couplers, with each coupler including respective pairs of coupled signal conductors. The signal conductors are connected sequentially in series between an input port and an output port and may form a single spiral configuration. A signal conductor of one coupler may be connected in series between the two signal conductors of another coupler. The couplers have characteristic impedances between an input impedance and an output impedance. A signal conductor of a coupler may include first and second conductor portions disposed in respective spaced-apart parallel planes, with the other signal conductor of the coupler disposed physically directly between the conductor portions. A signal conductor in the spiral may be shielded from coupled signal conductors by ground conductors disposed in respective spaced-apart parallel planes on opposite sides of the shielded signal conductor. The first and second couplers may have a shared signal conductor.

An architecture for, and techniques for fabricating, a thermal decoupling device are provided. In some embodiments, thermal decoupling device can be included in a thermally decoupled cryogenic microwave filter. In some embodiments, the thermal decoupling device can comprise a dielectric material and a conductive line. The dielectric material can comprise a first channel that is separated from a second channel by a wall of the dielectric material. The conductive line can comprise a first segment and a second segment that are separated by the wall. The wall can facilitate propagation of a microwave signal between the first segment and the second segment and can reduce heat flow between the first segment and the second segment of the conductive line.

An architecture for, and techniques for fabricating, a cryogenic microwave filter having reduced Kapitza resistance are provided. In some embodiments, the cryogenic microwave filter can comprise a substrate and a conductive line. The substrate can be formed of a material having a thermal conductivity property that sufficiently reduces Kapitza resistance in the cryogenic environment. The conductive line can be formed in a recess of the substrate and facilitate a filter operation on a microwave signal propagated in a cryogenic environment. In some embodiments, the conductive line can be formed according to a sintering technique that can reduce Kapitza resistance.