Gain in time-dependent media—a new mechanism

• DOI: 10.1364/josab.427682
• Publication Date: 2021-09-02T12:00:35Z
• Authors: J. B. Pendry; E. Galiffi; P. A. Huidobro
• Keywords: Intuition

Time-dependent systems do not in general conserve energy, invalidating much of the theory developed for static and turning our intuition on its head. This is particularly acute luminal space-time crystals, where structure moves at or close to velocity light. Conventional Bloch wave no longer applies, energy grows exponentially with time, a new perspective required understand phenomenology. In this paper, we identify mechanism amplification: compression lines force that are nevertheless conserved number.