Research: Topological Excitations on Commercial Circuit Boards Possible, and Simple, and Reconfigurable, and Highly Controllable

4-D electric circuit network with topology

Points to note…

+  In recent years, topology has emerged as an important tool to classify and characterize properties of materials. It has been found that many materials exhibit a number of unusual topological properties, which are unaffected by deformations, e.g., stretching, compressing, or twisting. These topological properties include quantized Hall currents, large magnetoresistance, and surface excitations that are immune to disorder. It is hoped that these properties could be utilized for future technologies, such as, low-power electronics, ultrafast detectors, high-efficiency energy converters, or for quantum computing.

The authors have performed detailed numerical simulations of the topological circuit network and have shown that the 3-D Weyl excitations can be readily observed in frequency-dependent measurements.

+  More recently, topology has been applied also to synthetic materials, e.g., photonic crystals or networks of electric circuits. These synthetic materials have several benefits compared to their natural counterparts. For example, the topology of their excitations (i.e., their excitation bands) can be precisely controlled and manipulated. In addition, due to their long-ranged lattice connectivity, synthetic materials can realize topological excitations in dimensions greater than three. Hence, synthetic materials, and in particular electric circuit networks, offer the possibility to realize a number of interesting topological properties that are not accessible in real materials.

+  The authors’ work demonstrates that topological excitations can be easily realized on commercially available circuit boards or integrated-circuit wafers composed of inductors and capacitors. It paves the way for realizing arbitrary types of topological surface excitations, for example, so-called Dirac or Majorana excitations of dimensions two, three, or even higher. The electric-circuit implementation of topological excitations has the advantage of being simple, easily reconfigurable, and allowing a high degree of control. This will make it possible to study in the future topological phase transitions, non-linear effects, out-of-equilibrium phenomena, and quantum open systems (e.g., non-Hermitian systems).

Source:  Science China Press,  4-D electric circuit network with topology…

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