Generation of four negative differential resistance regions using two resonant tunnelling diodes

In this paper we report on the experimental observation of four negative differential resistance regions in the current-voltage characteristic of a monolithically integrated seriesconnection of two resonant tunneling diodes at room temperature. An equivalent circuit of the seriesconnection is proposed which gives an explanation of the experimental results. The required current-voltage characteristics of the two resonant tunneling diodes in the seriesconnection, to generate the multiple negative resistance regions, are discussed. Simulations based on the equivalent circuit, show the possibility of five negative differential resistance regions with a monolithically integrated seriesconnection of two resonant tunneling diodes.