Abstract: The present invention relates to an electrically controllable/tunable microwave device comprising a ferroelectric substrate with a variable dielectric permitivity and conducting electrodes, arranged on said substrate, and the capacitance of which depends on applied voltage C/V), the microwave device comprises at least two sections or parts of the substrate/electrodes for each of which different electrical field strengths are generated upon voltage application. Said generated electrical field strengths are controlled by means of the design of the device and/or the voltage application such that the slope (dC(dV) of the voltage dependence of the capacitance (C(V) of the microwave device can be controlled.

Abstract: The present invention relates to a tunable resonating arrangement comprising a resonator apparatus (10), input/output coupling (4) means for coupling electromagnetic energy into/out of the resonator apparatus, and a tuning device (3) for application of a biasing voltage/electric field to the resonator apparatus. The resonator apparatus comprises a first resonator (1) and a second resonator (2). Said first resonator is non-tunable and said second resonator is tunable and comprises a ferroelectric substrate (21). Said first and second resonators are separated by a ground plane (13) which is common for said first and second resonators, and coupling means (5) are provided for providing coupling between said first and second resonators. For tuning of the resonator apparatus, the biasing voltage/electric field is applied to the second resonator (2).

Abstract: The present invention relates to an electrically controllable/tunable microwave device comprising a ferroelectric substrate with a variable dielectric permitivity and conducting electrodes, arranged on said substrate, and the capacitance of which depends on applied voltage C/V), the microwave device comprises at least two sections or parts of the substrate/electrodes for each of which different electrical field strengths are generated upon voltage application. Said generated electrical field strengths are controlled by means of the design of the device and/or the voltage application such that the slope (dC(dV) of the voltage dependence of the capacitance (C(V) of the microwave device can be controlled.

Abstract: The present invention relates to an electrically controllable/tunable microwave device comprising a ferroelectric substrate with a variable dielectric permitivity and conducting electrodes, arranged on said substrate, and the capacitance of which depends on applied voltage C/V), the microwave device comprises at least two sections or parts of the substrate/electrodes for each of which different electrical field strengths are generated upon voltage application. Said generated electrical field strengths are controlled by means of the design of the device and/or the voltage application such that the slope (dC(dV) of the voltage dependence of the capacitance (C(V) of the microwave device can be controlled.

Abstract: The present invention relates to a tunable resonating arrangement comprising a resonator apparatus (10), input/output coupling (4) means for coupling electromagnetic energy into/out of the resonator apparatus, and a tuning device (3) for application of a biasing voltage/electric field to the resonator apparatus. The resonator apparatus comprises a first resonator (1) and a second resonator (2). Said first resonator is non-tunable and said second resonator is tunable and comprises a ferroelectric substrate (21). Said first and second resonators are separated by a ground plane (13) which is common for said first and second resonators, and coupling means (5) are provided for providing coupling between said first and second resonators. For tuning of the resonator apparatus, the biasing voltage/electric field is applied to the second resonator (2).

Abstract: The present invention relates to an electrically controllable/tunable microwave device (10) comprising a ferroelectric substrate (101) with a variable dielectric permittivity and conducting electrodes (102, 103A-C), arranged on said substrate, and the capacitance of which depends on applied voltage C(V), the microwave device comprises at least two sections or parts of the substrate/electrodes for each of which different electrical field strengths are generated upon voltage application. Said generated electrical field strengths are controlled by means of the design of the device and/or the voltage application such that the slope (dC(dV) of the voltage dependence of the capacitance (C(V)) of the microwave device can be controlled.

Abstract: A thin film ferroelectric varactor device comprising a substrate layer, a ferroelectric layer structure and an electrode structure is presented. The ferroelectric layer structure comprises a number of ferroelectric layers and a number of intermediate buffer layers arranged in an alternating manner. At least a first and a second layer of the ferroelectric layers have different Curie temperatures, i.e. the dielectric constant of the first ferroelectric layer has a maximum at a temperature which is different from the temperature at which the dielectric constant of the second ferroelectric layer has a maximum.

Abstract: An inductor for microwave frequencies has a substantially planar structure and is constructed of a transmission line designed as a linear microstrip element made of a central line comprising normal electrically conducting material, such as a suitable metal. The microstrip element has a width which is varied by making areas at sides of the central line superconducting. By changing the effective width of the microstrip, the inductance of the microstrip is changed accordingly. The areas at the sides of the microstrip element in the non-superconducting state may have some electrical conductivity. However, because they contact the central metal conductor only at a very narrow edge, instead of contacting it at a large surface, the side superconducting areas do not significantly affect the transmission characteristics of the transmission path when the superconducting areas are in the normal state.

Abstract: A magnetoresistive element, comprising a crystal structure with a grain boundary formed at a misorientation angle, and a method of producing a crystal structure having colossal magnetoresistance, wherein a grain boundary is formed at a misorientation angle. The crystal structure comprises a substrate layer and a CMR film layer epitaxially grown thereon, the CMR film layer having a plurality of first sections and a plurality of second sections with intermediate grain boundaries, the crystallographic axis of the first sections being different from the crystallographic axis of the second sections.

Abstract: A microwave device includes a number of parallel-plate resonators that include at least one dielectric substrate and first and second plates arranged on either side of the substrate. At least one of the plates of each of a number of the parallel-plate resonators includes a current interrupting device such that the current lines of at least one undesired mode are interrupted at their maxima to suppress the undesired mode. There is also described a method of interrupting undesired modes in a microwave device having a number of parallel-plate resonators.

Abstract: A superconducting substrate structure with a high temperature superconducting (HTS) ground plane, for epitaxial growth of multilayers thereon is provided. The substrate structure includes a composite substrate structure with a first and a second substrate layer each covered by an HTS film, which HTS films are bonded together through annealing to form a buried superconducting layer wherein one of the substrate layers is polished to form a smooth insulating layer adjacent to an HTS layer. A method of producing a superconducting substrate structure is provided including the steps of arranging two substrate layers on which HTS films are provided such that the HTS films come in close contact to one another, applying a high pressure in an oxygen atmosphere and at an elevated temperature such that the HTS films are annealed and bonded together, and subsequently polishing one of the substrate layers to form a smooth insulator.

Abstract: A tunable microwave device has a substrate of a dielectric material which has a variable dielectric constant. At least one superconducting film is arranged on at least parts of the dielectric substrate. The dielectric substrate includes a non-linear dielectric bulk material.

Abstract: An electrically tunable device, particularly for microwaves, includes a carrier substrate, conductors, and at least one tunable ferroelectric layer. Between the conductors and the tunable ferroelectric layer, a buffer layer including a thin film structure having a non-ferroelectric material is arranged.

Abstract: An inductor for microwave frequencies has a substantially planar structure and is constructed of a transmission line designed as a linear microstrip element made of a central line comprising normal electrically conducting material, such as a suitable metal. The microstrip element has a width which is varied by making areas at sides of the central line superconducting. In changing the effective width of the microstrip the inductance thereof is changed accordingly. The areas at the sides of the microstrip element are located directly at the central, normal metal conductor. These areas have in the non-superconducting state some electrical conductivity which can be rather low but owing to the fact that they contact the normal central metal conductor only at a very narrow edge instead of contacting it at a large surface they do not significantly affect the transmission characteristics of the transmission path when the superconducting areas are in their normal state.

Abstract: The present invention relates on an interferometer arrangement comprising a source electrode and a drain electrode, a base electrode to which the source electrode and the drain electrode are connected through tunnel barriers, the base electrode thus forming a double barrier quantum well, and first and second superconducting gate electrodes to control the source-drain current. The base electrode comprises a ferromagnetic material enabling resonant tunneling of source-drain electrons when there are bound states within the quantum well structure matching the energy of said source-drain electrons. The invention also relates to a logical element comprising such an interferometer arrangement and to a method of controlling the conductance of an interferometer.

Abstract: The present invention relates to a thin film ferroelectric varactor device (10) comprising a substrate layer (1), a ferroelectric layer structure (12) and an electrode structure (91,92). The ferroelectric layer structure (12) comprises a number of ferroelectric layers (2,4) and a number of intermediate buffer layers (3) arranged in an alternating manner. At least a first (2) and a second (4) layer of said ferroelectric layers have different Curie temperatures, i.e. the dielectric constant of the first ferroelectric layer (12) has a maximum at a temperature which is different from the temperature at which the dielectric constant of the second ferroelectric layer (4) has a maximum.

Abstract: A tunable microwave monolithic integrated circuit includes a dielectric material with a variable dielectric constant. A superconducting material with a negative dielectric constant is provided which is arranged in relation to the dielectric material in such a way that at least one interface is formed between the superconducting material and the dielectric material. The dielectric material is a low loss non-linear bulk material. Phase velocity tuning of microwaves is provided through controlling the propagation of surface plasma waves of the microwaves along the interface(s).

Abstract: A logic circuit arrangement includes signal input and signal output devices and a number of SFQ circuits having Josephson junctions in which carrier devices are used for carrying digital information. The SFQ circuits are sampled at the input/output for producing DC voltages and a train having at least two single flux quanta is used as a carrier device for information and phase locking between at least two Josephson junctions is used to provide at least two different dynamic states of which at least one provides an output signal.

Abstract: An arrangement for coupling electro magnetic waves, particularly microwaves, into and/or out of a device which includes a dielectric resonator having a non-linear dielectric substrate with a high dielectric constant and a coupling loop. The dimensions of the resonator and the coupling loop are related to the resonant frequency of the resonator. The coupling loop is so arranged in relation to the resonator that the magnetic field lines around the coupling loop match the internal film distribution of at least one mode, which has been selected to be excited, so that only that mode is excited. Coupling is provided only for this mode. The length of the coupling loop is comparable to or larger that the dimensions of the resonator.

Abstract: Superconducting multiplexing/demultiplexing arrangements include a number of signal input devices and a number of signal output devices. A number of resonators provides a number of filters. Each filter represents a channel. The resonator(s) operate(s) devices at lest in dual mode, and tuning devices are provided so that at least some of the resonators is/are tuneable. A method is provided of multiplexing signals incoming to a multiplexing arrangement with a number of resonators, each of the resonators having a number of input ports which are so arranged that a number of mulitpole filters are created. Input signals having different frequencies are supplied to the different input ports of the resonators, each of which is operated in three modes. Coupling devices are arranged which at least comprise the angle between the input ports and a symmetry plane. The angles are non-perpendicularly azimuth.