Operation of a Quantum Free Electron Laser (QFEL) could provide compact and fully coherent source X- γ-rays. Imperative to experimental realization is allowing for decoherence effects either spontaneous emission or space-charge take place, having opposing constraints. Here, the first time, we present one-dimensional QFEL Wigner model that includes longitudinal by quantizing periodic potential d...

Harmonic lasing of low-gain free electron laser oscillators has been experimentally demonstrated in the terahertz and infrared regions. Recently, the low-gain oscillator has been reconsidered as a promising candidate for hard x-ray free electron lasers, through the use of high reflectivity, high-resolution x-ray crystals. In this Letter, it is proposed to utilize a crystal-based cavity resonant...