Are repair shops for electronic devices about to become extinct?

It's hard to imagine the world without electronics. Computers, smartphones, advanced commerce, medicine and transportation are all based on electronic systems and components. However, advanced electronic components and devices are prone to production defects and wear over time.  This is the main reason for breakdowns after a while. Is it possible to design electronic devices that are not susceptible to wear and failure, and never break down? This question intrigued Dr. Yakir Hadad of TAU's School of Electrical Engineering. Together with Prof. Andrea Alù and Dr. Jason Zorik of UTEXAS and Prof. Alexander Khanikaev of CUNY, he looked for a creative solution to the problem.

The connection between electrical circuits and soccer

As often happens, the idea for a solution came from a totally different direction – Materials Science. The Nobel Prize in Physics for 2016 was awarded to three British researchers for showing that properties of materials, for example electrical conductivity, can be preserved under certain conditions even when the shape of the material is significantly damaged. This wonderous capability stems from the material's specific atomic structure and is closely connected to a mathematical field called topology. Topology deals with the geometrical properties of a surface or body that are preserved even when its shape is altered, as long as the deformation is continuous (with no holes formed). Topology attributes a topological number to every object, which essentially denotes the number of holes in it. The topological number of a soccer ball, for example, is 0. A cube and a glass (without a handle) also have a topological number of 0. Thus, in topological terms, these are all equivalent objects. A bagel and a cup (with a handle), on the other hand, have a topological number of 1 because they have one hole, and are therefore not equivalent (topologically) to a glass or a soccer ball. Consequently, it appears that if a topological number can somehow be attributed to a material, some of its properties will not change in case of shrinking, stretching or bending (namely defects), as long as its topology is preserved.

New design for dependable electronic devices

This complex idea has been applied in recent years in various areas – optics, magnetism and more, to design and produce special devices that are immune to structural flaws. In the study published in March 2018 in Nature Electronics, Dr. Hadad and his colleagues demonstrated that a similar effect can be achieved in electrical circuits. Moreover, the immunity to defects can be induced by the electrical current itself as it runs through the circuit, by using the nonlinear properties of the circuit's components (the components' properties change in correlation with the current's intensity). Based on this idea, the researchers designed and built an electronic device which, when a sufficiently powerful current runs through it, become essentially indifferent to defects. The researchers also demonstrated the operation of the device, showing that even when substantial defects were intentionally introduced into the structure, they had no effect on the circuit's proper functioning. The study's results open a window onto a new approach to designing more dependable, defect-resistant electronic devices, while demonstrating that combining ideas from different worlds and disciplines can lead to creative solutions for real-world problems.