The Detectors Used in the First Radios Were Memristors

Abstract

The recent discovery of memristor has sparked renewed interest in the scientific community about state dependent resistances. In the current paper, we show that the detector used in the first radios, called cat’s whisker, had memristive properties. We have identified the state variable governing the resistance state of the device and can program it to switch between multiple stable resistance states. Our observations are valid for a larger class of devices called coherers, including cat’s whisker. We further argue that these constitute the missing canonical physical implementations for a memristor.