[sdiy] Negative resistance elements

[cheater cheater]

Hi all, a recent conversation about tunnel diodes brought me to the
question of something like this could be useful with synthesizer
design. Putting aside the fact that they are currently very rare, are
the unique characteristics of this kind of device useful?
Specifically, they have a negative resistance segment in their I/V
curve. The curve rises (positive resistance), then falls (negative
resistance), then rises again.

This article explains tunneling diodes pretty well:
https://www.electronicshub.org/tunnel-diode-working-characteristics-applications/

and here is the I/V curve:
https://www.electronicshub.org/wp-content/uploads/2018/10/Tunnel-Diode-I-V-Characteristics.jpg

I know for one thing tunnel diodes were used to make very fast
oscillators, schmitt triggers, and flip-flops, but other than that,
are there any other uses where they could be used?

Thanks