Soft X-ray source for nanostructure imaging using femtosecond-laser-irradiated clusters

Fukuda, Yuji; Faenov, A. Y.; Pikuz, T. A.*; Kando, Masaki; Kotaki, Hideyuki; Daito, Izuru; Ma, J.-L.; Chen, L. M.; Homma, Takayuki; Kawase, Keigo; Kameshima, Takashi; Kawachi, Tetsuya; Daido, Hiroyuki; Kimura, Toyoaki; Tajima, Toshiki; Kato, Yoshiaki ; Bulanov, S. V.

The novel soft X-ray light source using the supersonic expansion of the mixed gas of He and CO, when irradiated by a femtosecond Ti:sapphire laser pulse, is observed to enhance the radiation of soft X-rays from the CO clusters. Using this soft X-ray emissions, nanostructure images of 100-nm thick Mo foils in a wide field of view (mm scale) with high spatial resolution (800 nm) are obtained with high dynamic range LiF crystal detectors. The local inhomogeneities of soft X-ray absorption by the nanometer-thick foils is measured with an accuracy of less than 3 %.