Ladder Climbing and Autoresonant Acceleration of Plasma Waves

TL;DR

This paper explores how modulating plasma density can induce ladder-like energy growth in plasma waves, enabling controlled energy transfer through classical analogs of quantum ladder climbing and autoresonance.

Contribution

It introduces a universal Lagrangian framework predicting ladder climbing and autoresonance effects for linear waves in plasma and other media, bridging classical and quantum analogies.

Findings

Discrete plasmon modes can be coupled via density modulation.

Energy can be up- or down-converted in a ladder-like manner.

Continuous autoresonance allows manipulation of plasmons with chirped modulations.

Abstract

When the background density in a bounded plasma is modulated in time, discrete modes become coupled. Interestingly, for appropriately chosen modulations, the average plasmon energy might be made to grow in a ladder-like manner, achieving up-conversion or down-conversion of the plasmon energy. This reversible process is identified as a classical analog of the effect known as quantum ladder climbing, so that the efficiency and the rate of this process can be written immediately by analogy to a quantum particle in a box. In the limit of densely spaced spectrum, ladder climbing transforms into continuous autoresonance; plasmons may then be manipulated by chirped background modulations much like electrons are autoresonantly manipulated by chirped fields. By formulating the wave dynamics within a universal Lagrangian framework, similar ladder climbing and autoresonance effects are predicted to be achievable with general linear waves in both plasma and other media.