Resonant tunneling diode memristor

In 1994, F. A. Buot and A. K. Rajagopal of the U.S. Naval Research Laboratory demonstrated [28] that a ‘bow-tie’ current-voltage (I-V) characteristics occurs in AlAs/GaAs/AlAs quantum-well diodes containing special doping design of the spacer layers in the source and drain regions, in agreement with the published experimental results. This ‘bow-tie’ current-voltage (I-V) characteristic is sine qua non of a memristor although the term memristor is not explicitly mentioned in their papers. No magnetic interaction is involved in the analysis of the ‘bow-tie’ I-V characteristics.