Complex nonlinear dynamical systems have been appeared in many fields of science and engineering. We are curious about two specific instances of those systems. Those two instances connect memristors and Josephson junctions to the electromagnetic fields. The first instance investigated microstrip patch antenna embedding dual memristors. This hybrid system produces broadband radiation in a narrow band radiation structure. The second one studies the novel ultra-sensitive magnetic field receiver implemented by superconducting quantum interference filters (SQIFs).
For the first instance, we notice that memristor has been proposed as the fourth passive element. We start with investigating the circuit model of this memristive element. Then, we embedded this circuit model into an EM radiation structure. We first report an efficient broadband electromagnetic radiation from a narrowband microstrip patch antenna. The directly modulated microstrip patch antenna system with dual memristors is calculated by using an integrated full-wave finite-difference time-domain solver and an embedded SPICE3 solver. Nonlinear transient electromagnetic responses are analyzed. The radiation frequency spectrum demonstrates the broadband radiation performance from the narrowband antenna system. We predict that the conceptual challenge of high frequency memristors will stimulate pioneering work in the fields of microwave and memristors.
For the second one, we predict that superconducting quantum interference filters (SQIFs) might play a key role in future quantum wireless communication systems. We analyze the dynamic behavior of this large-scale 2D DC SQIF (two-dimensional superconducting direct current quantum interference filter) array in a dynamic electromagnetic environment. The investigation under this framework starts from the SPICE circuit description of a RCSJ (resistively and capacitively shunted junction) model of a Josephson junction and then extends to the 2D SQIF with few device parameters. We separate the interface and the implementation of 2D DC SQIF. This approach can significantly improve circuit-level design efficiency of 2D SQIF array and ultimately allows us to accelerate the hybrid design with an electromagnetic radiation structure. Our findings on the average voltage response of this device offer compelling evidence that the bias static magnetic field plays a key role in designing an effective far-field magnetic field sensor. Since this device can function as both a robust and sensitive low noise pre-amplifier as well as a receiving antenna which only senses the magnetic field component of far-field electromagnetic wave signals, we call it magnetic-antenna or B-antenna. We believe that our research not only directly benefits the sensor design for Information Operations/Signals Intelligence (IO/SIGINT) applications in Very High Frequency/Ultra High Frequency (VHF/UHF) bands, but also opens new dimension of novel ultra-sensitive receiving antenna technology.
