Wave Frequency Multipliers Research Articles

Submillimeter Wave High Order Frequency Multiplier Based on Graphene

In this paper, a single stage millimeter/submillimeter wave frequency multiplier is presented. The desired frequency multiplication performance is obtained through the nonlinear excitation of high-order harmonic components in a graphene film, when it is illuminated with a low-frequency input signal. The graphene film is integrated into a microstrip structure on a polyimide substrate, which is subsequently embedded in a micromachined waveguide block. The design has been optimized to receive an input signal in the Ka frequency band, between 26.5 and 40 GHz, and to produce an output signal in the WR-3 frequency band, between 220 and 330 GHz. A complete prototype of the frequency multiplier module, including standard waveguide flanges for its interconnection, has been manufactured and experimentally characterized. The results in terms of output power in the WR-3 frequency band, for harmonic orders between 6 and 11, as well as for input power levels between 7 and 21 dBm, are presented.

Linear and nonlinear spin-wave dynamics in ultralow-damping microstructured Co2FeAl Heusler waveguide

We report on the investigation of linear and nonlinear spin-wave dynamics of a microstructured Co2FeAl Heusler waveguide using the microfocus Brillouin light scattering technique. A significantly increased decay length of 19.55 μm owing to decreased Gilbert damping has been observed for waves propagating in the linear regime. Furthermore, the localized edge mode caused by the demagnetizing field leads to the nonlinear generation of high-order harmonics at double and triple excitation frequencies at high powers. The obtained results provide valuable insights into the linear and nonlinear spin wave dynamics of the Heusler waveguide and could potentially be applied in the implementation of spin wave frequency multipliers for magnonic applications.

A GaAs planar Schottky varactor diode for left-handed nonlinear transmission line applications

The left-handed nonlinear transmission line (LH-NLTL) based on monolithic microwave integrated circuit (MMIC) technology possesses significant advantages such as wide frequency band, high operating frequency, high conversion efficiency, and applications in millimeter and submillimeter wave frequency multiplier. The planar Schottky varactor diode (PSVD) is a major limitation to the performance of the LH-NLTL frequency multiplier as a nonlinear component. The design and the fabrication of the diode for such an application are presented. An accurate large-signal model of the diode is proposed. A 16 GHz-39.6 GHz LH-NLTL frequency doubler using our large-signal model is reported for the first time. The measured maximum output powers of the 2nd harmonic are up to 8 dBm at 26.4 GHz, and above 0 dBm from 16 GHz to 39.6 GHz when the input power is 20 dBm. The application of the LH-NLTL frequency doubler furthermore validates the accuracy of the large-signal model of the PSVD.

Millimeter Wave Solid State Devices

ABSTRACTExamples of novel solid state devices are presented, together with descriptions of their applicability to the diagnosis of laboratory, processing and fusion plasmas. GaAs varactor diodes can be arranged in large monolithic grid arrays, forming millimeter wave frequency multiplier based sources and high speed switches, or embedded in transmission lines to provide a true time delay for phased antenna array beam steering. Micro-electromechanical systems (MEMS) switches are exciting new devices with numerous applications, including low loss millimeter wave switches, phase shifters and mechanically tunable structures.