In recent years there has been an increasing interest in using narrow-band mid-IR and THz-frequency pulses to drive materials into nonequilbirium regimes with qualitatively different properties than those seen in equilibrium. To study these nonequilibrium states, the ultrafast x-rays produced at SwissFEL are an important potential tool for understanding how these properties can be controlled. An important prerequisite for using the SwissFEL in this context is the ability to produce mid-IR frequency pulses with so-called "carrier envelope" phase stability, where the oscillation phase of the electric field has a fixed time with respect to the intensity envelope of the laser. Scientists in LNO have recently successfully installed a passively CEP stable mid-IR source at the Bernina endstation at SwissFEL. The new pump source should be ready to use with experiments in 2020.
Contact person: Yunpei Deng (yunpei.deng@psi.ch)