An interface between cryogenic computational hardware and room temperature computational hardware includes a plurality of discrete stages, including a first stage at room temperature and a last stage at a cryogenic temperature. Each successive stage is configured for operation at a corresponding refrigeration temperature that is lower than the refrigeration temperature of each preceding stage and includes a set of planar transmission lines. The transmission lines of any given stage other than the first stage are proximally coupled to and contiguous with the transmission lines of an immediately preceding stage. The transmission lines of the first stage are proximally coupled to the room temperature computational hardware, and the transmission lines of the last stage are proximally coupled to the cryogenic computational hardware. Each stage has shielding configured to block electromagnetic radiation external to such stage.

A circuit arrangement and methods for reducing a switching noise jitter signature in an output signal of a feedback control loop circuitry are disclosed. The passive signal conditioning means including the rails is closely coupled to the common connection junction and is characterized by a set of specified characteristics to condition pre-existing noise amplitude and slopes of the output signal so as to improve the interactions between the output signal and the feedback control loop circuitry. As a consequence, the switching noise jitter signature, which is produced by transient noise displacement or noise perturbation in the time domain when the output signal jitters, can be reduced in the output of the feedback control loop circuitry.

A variable attenuator is an attenuator which is formed by coupling two transmission lines having an electrical length of /4 corresponding to a wavelength of an input signal, has one end of one transmission line as an input terminal, has the other end of the one transmission line as a through terminal, has one end of the other transmission line as a coupling terminal and has the other end of the other transmission line as an output terminal, wherein the variable attenuator has a resistor pair having the same impedance at both the through terminal and the coupling terminal, and has a resistor pair having the same impedance at both the input terminal and the output terminal.

The technology described herein is directed towards a cryogenic-stripline microwave attenuator. A first high thermal conductivity substrate such as sapphire and a second high thermal conductivity substrate such as sapphire, along with a signal conductor comprising one or more attenuator lines between the substrates form a stripline. A compression component such as one or more screws, vias (plus clamps) and/or clamps presses the first high thermal conductivity substrate against one side of the signal conductor and presses the second high thermal conductivity substrate against another side of the signal conductor. The high thermal conductivity of the substrates facilitates improved thermalization, while the pressing of the substrates against the conductor reduces the thermal boundary (Kapitza) resistance and thereby, for example, improves thermalization and reduces thermal noise.

A resistive flex microwave attenuator for coupling control signals to a quantum computational hardware system includes a set of planar transmission lines, each such planar transmission line having first and second ends along a longitudinal axis. Each such planar transmission line includes: a set of ground planes disposed in a direction parallel to the longitudinal axis; a dielectric disposed in a direction parallel to the longitudinal axis and in contact with the set of ground planes; a signal line disposed in a direction parallel to the longitudinal axis and in contact with the set of ground planes; a metallic layer disposed around the set of ground planes; an input, coupled to such planar transmission line at the first end, and configured to receive the control signals; and an output, coupled to such planar transmission line at the second end, and configured for coupling to the quantum computational hardware system. At least one member selected from the group consisting of a ground plane of the set of ground planes and the signal line is resistive to provide attenuation. The set of planar transmission lines has a geometry configured for dissipation of heat, attributable to energy provided at the input, in a manner distributed along a length of the set of planar transmission lines. The set of planar transmission lines provide attenuation, without recourse to discrete components, across a desired frequency band. If there are a plurality of planar transmission lines, the set of planar transmission lines is disposed so that their respective ground planes are approximately coincident.

A force-controlled-switch comprises a diaphragm spring element and an absorber-plate. The absorber-plate is configured to absorb kinetic energy of the force-controlled-switch. In particular, the absorber-plate absorbs a part of the diaphragm-spring-element's kinetic energy.

The present disclosure provides a signal conditioner, an antenna device and a manufacturing method. The signal conditioner includes: a microstrip line including a first portion and a second portion; an insulating layer including a first insulating layer covering the first portion; at least one electrode; a liquid crystal layer covering the microstrip line, the insulating layer, and the at least one electrode; and a common electrode line. A first end of the first portion is connected to a first end of the second portion. A second end of the first portion is connected to a second end of the second portion. The at least one electrode includes a first electrode on a side of the first insulating layer facing away from the first portion. The common electrode line is on a side of the liquid crystal layer facing away from the microstrip line.

A variable RF attenuator includes a substrate, a first microstrip trace, a first thin film resistor, a second microstrip trace, and a wire bond. The substrate includes a dielectric layer. The first thin film resistor is disposed on the substrate. The first microstrip trace is disposed on the substrate and the first thin film resistor. The second microstrip trace is disposed on the substrate and is uncoupled from the first microstrip trace. The wire bond extends from the second microstrip trace to a position on the first microstrip trace. The position is selected to tune RF attenuation over a conductive path defined by the first microstrip trace, the wire bond, and the second microstrip trace.

A variable attenuator is an attenuator which is formed by coupling two transmission lines having an electrical length of /4 corresponding to a wavelength of an input signal, has one end of one transmission line as an input terminal, has the other end of the one transmission line as a through terminal, has one end of the other transmission line as a coupling terminal and has the other end of the other transmission line as an output terminal, wherein the variable attenuator has a resistor pair having the same impedance at both the through terminal and the coupling terminal, and has a resistor pair having the same impedance at both the input terminal and the output terminal.

A resistive component in a hybrid microwave attenuator circuit is configured to attenuate a plurality of frequencies in an input signal. The hybrid microwave attenuator circuit is further configured with a dispersive component to attenuate a second plurality of frequencies within a frequency range by reflecting off portions of the input signal at those frequencies that are within the frequency range. The resistive component and the dispersive component are arranged in a series configuration relative to one another in the hybrid microwave attenuator circuit.