Wavebreaking-associated transmitted emission of attosecond extreme-ultraviolet pulses from laser-driven overdense plasmas

Abstract

We present a new mechanism of attosecond extreme-ultraviolet (XUV) pulses generation from a relativistic laser-driven overdense plasma surfaces in the wavebreaking regime. Through particle-incell simulations and analysis, we demonstrate that the observed ultrashort XUV emission for the parameters we considered is predominantly due to a strong plasma-density oscillation subsequent to wavebreaking. The coupling of the strong density variation and the transverse fields in the front surface layer gives rise to the transmitted emission with frequencies mainly around the local plasma frequency. This mechanism provides new insights into the scenarios of XUV generation from solid surfaces and the dynamics of laser-plasma interactions.

Electron trajectories associated with laser-driven coherent synchrotron emission at the front surface of overdense plasmas

“…[22]), the forward emission mechanism is fundamentally different from that associated with wave breaking as discussed in Refs. [27,34].…”

Electron Dynamics and Characteristics of Attosecond Electromagnetic Emissions in Relativistic Laser-Plasma Interactions

“…Chen et al also investigated the effects of the density gradient of plasma foil targets and those of multi dimensions on the XUV pulse generation. [17] In summary, the electron dynamics and the associated generation of attosecond EM pulses have been studied with the wavebreaking process when one intense laser pulse normally irradiates on a dense plasma foil target. Two distinct electron bunches closely related to the wavebreakings are observed to emit attosecond pulses in both the reflection and the transmission.…”

“…[9,13,15] A complicated generation process of attosecond XUV pulses is reported as the wavebreaking associated transmitted emission (WTE) by Chen et al in the study of a relativistic laser pulse irradiating on an overdense plasma surface. [17] It is found that the strong wavebreaking process of the plasma generates XUV pulses in the transmitted direction. However, the detailed process of the EM pulse generation associated with the wavebreaking is not discovered in that work.…”

The effects of plasma density-gradient on laser-driven transmitted emission

“…However, the limitation on laser intensity implies that the emitted harmonic pulse energy is also limited. One way to break through this limitation is to generate attosecond pulses using solid target [8][9][10][11][12][13][14][15][16]. After irradiated by an intense laser, the target becomes plasmas and can withstand laser intensity of 10 18 W cm −2 and even higher.…”