How does negative power link to amplification?

[Dan15]

So I've been studying electrons behavior in a semiconductor superlattice and I am currently analyzing the negative slope for the drift velocity against electric field. This is where negative differential velocity (NDV) takes place. I understand how NDV leads to negative power, but I can't quite grasp how that would relate to amplification?

Any help or points in the right direction would be great!

 

[BigJDubs]

Negative differential velocity (NDV) can be used to amplify signals in an electronic circuit. This is because when there is a negative slope in the drift velocity vs electric field curve, the electrons can be accelerated more efficiently for a given voltage. This means that a smaller input voltage can result in a larger output voltage, resulting in signal amplification. Additionally, NDV can be used to create oscillations in a circuit, since it acts like an oscillator. By using NDV, it is possible to generate and amplify signals that can be used in various applications such as communications, audio, imaging, and sensing.