Enhancement of the free-electron coherent harmonic generation by use of the dispersive function on a storage ring

Abstract

An alternative to the free electron laser (FEL) oscillator at short wavelengths (λ < 2000 Å) is the “coherent harmonic generation” (CHG) process with an external laser. However, this coherent emission is rather weak, particularly on high harmonics (n ⩾ 5). This paper shows that the introduction of an “energy-dispersive function” on a storage ring increases the CHG by several orders of magnitude.