A beam steered phased array antenna and system for including the same are described. In one embodiment, the antenna apparatus comprises an array of a plurality of antenna elements, the array having a single moveable feeding point coupled to the antenna elements, where the moveable feeding point is movable with respect to the antenna elements in the array.

A voltage-controlled magnetic based device is described that includes a magnetic insulator; a topological insulator adjacent the magnetic insulator; and magnetic dopants within the topological insulator. The magnetic dopants are located within an edge region of the topological insulator to inhibit charge current flow in the topological insulator during a switching operation using an applied electric field generating by applying a switching voltage across two electrodes at opposite sides of the topological insulator. Power dissipation due to carrier-based currents can be avoided or at least minimized by the magnetic dopants at the edges of the topological insulator.

A voltage-controlled magnetic based device is described that includes a magnetic insulator; a topological insulator adjacent the magnetic insulator; and magnetic dopants within the topological insulator. The magnetic dopants are located within an edge region of the topological insulator to inhibit charge current flow in the topological insulator during a switching operation using an applied electric field generating by applying a switching voltage across two electrodes at opposite sides of the topological insulator. Power dissipation due to carrier-based currents can be avoided or at least minimized by the magnetic dopants at the edges of the topological insulator.

A cryostat includes a magnet arrangement for the generation of a magnetic field B0, the magnet arrangement comprising an LTS portion having at least one LTS section made from a conventional low-temperature superconductor and an HTS portion having at least one HTS section made from a high-temperature superconductor. The HTS portion is arranged radially within the LTS portion, and the cryostat is designed to control the temperature of the LTS portion and the HTS portion independently of one another, wherein the HTS portion is electrically isolated from the LTS portion, and is designed to be superconductingly short-circuited. The invention proposes a cryostat with magnet arrangement which enables a high magnetic field strength in a compact space and, at the same time, can be easily constructed.

The invention relates to a gate unit (22) for controlling a gate commutated thyristor (21), comprising: a voltage selector (26) for selectively applying a high supply potential (V.sub.pos), a middle supply potential (V.sub.mid), and a low supply potential (V.sub.neg); a nonlinear inductor (27) serially coupled between the output of the voltage selector (26); a gate control unit (23) configured to control the voltage selector (26) to control switching of the gate commutated thyristor (21) in its turn-on state comprising a turn-on pulse generation, a positive-gate-voltage backporch operation, a negative-gate-voltage backporch operation and a retrigger pulse generation; wherein the nonlinear inductor (27) has a nonlinearity to have a high inductance during any of the backporch operations and to have a low inductance during the turn-on pulse generation and retrigger pulse generation.

Circuits and methods for increasing the long-term reliability and performance of phase change material (PCM) switches. To overcome the effects of electromigration damage of the resistive heater(s) of a PCM switch and of the PCM itself, and thus improve long-term performance and reliability, embodiments apply an AC control pulse of equal power to a conventional DC control pulse. An embodiment encompasses a PCM switch, including a PCM region including first and second signal ports configured to be coupled to a signal source; a resistive heater adjacent the PCM region and including first and second heater control signal ports; and a source of AC control pulses coupled to the first and second heater control signal ports, the AC control pulses having a first power profile to transform the PCM region into a low resistance state and a second power profile to transform the PCM region into a high resistance state.

Methods and devices for reading and programming a state of a switch device are presented. The programming of the state of the switch device is performed by providing driving pulses to the switch device. The amplitude and the width of the driving pulses are a function of one or more of a) temperature of the switch device, b) desired state of the switch device, and c) operational time of the switch device. The described devices include a device to store the data demonstrating the functional relation between the amplitude and the width of the driving pulses and the temperature of the switch device. Such device can be a lookup table or an arithmetic logic unit (ALU). The disclosed switch devices can be PCM switches.

Methods and devices for reading and programming a state of a switch device are presented. The programming of the state of the switch device is performed by providing driving pulses to the switch device. The amplitude and the width of the driving pulses are a function of one or more of a) temperature of the switch device, b) desired state of the switch device, and c) operational time of the switch device. The described devices include a device to store the data demonstrating the functional relation between the amplitude and the width of the driving pulses and the temperature of the switch device. Such device can be a lookup table or an arithmetic logic unit (ALU). The disclosed switch devices can be PCM switches.

A device structure includes a first series connection of a first phase change memory (PCM) switch and a second PCM switch. The first PCM switch includes a first heater line, a first PCM line, and a first contact electrode and a second contact electrode located on the first heater line. The second PCM switch includes a second heater line, a second PCM line, and a third contact electrode and a fourth contact electrode located on the second heater line. The second contact electrode is electrically connected to the third contact electrode. The fourth contact electrode is electrically grounded. One of the first contact electrode and the second contact electrode includes an radio-frequency (RF) signal input port. Another of the first contact electrode and the second contact electrode comprises an RF signal output port. The device structure may function as a combination PCM switch that decreases noise level during signal transmission.

A device structure includes a first series connection of a first phase change memory (PCM) switch and a second PCM switch. The first PCM switch includes a first heater line, a first PCM line, and a first contact electrode and a second contact electrode located on the first heater line. The second PCM switch includes a second heater line, a second PCM line, and a third contact electrode and a fourth contact electrode located on the second heater line. The second contact electrode is electrically connected to the third contact electrode. The fourth contact electrode is electrically grounded. One of the first contact electrode and the second contact electrode includes an radio-frequency (RF) signal input port. Another of the first contact electrode and the second contact electrode comprises an RF signal output port. The device structure may function as a combination PCM switch that decreases noise level during signal transmission.