Comparative Analysis of Different Techniques for Controlling Ratchet Effect in a Periodic Array of Asymmetric Antidots

摘要

We report a performance comparison between different techniques for enhancing and controlling the ratchet effect recently observed in arrays of asymetric antidots. Under microwave linear polarized radiation, the effect was observed in a high mobility two dimensional electron gas based on AlGaAs/GaAs heterojunction, with periodic array of artificial semi-discs shaped antidots. The uniformity of the incident electric field polarization, the uniformity of the incident power density, as well as the amount of the incident power flow across the surface of the semiconductor sample are the important parameters for choosing the suitable millimeter-wave illumination technique. Several techniques based on the use of horn antenna, dielectric lens or planar dielectric multilayer structures are analyzed in this communication. A comparative study based on full wave electromagnetic simulation allows us to identify the most suitable techniques for improving the original setup used for ratchet experiments. To our knowledge, this opens new possibilities of high frequency detectors based on ratchet effect in the millimeter and sub-millimeter wave region.