UFI’s single-shot phasemeter facilitates single-shot measurements of the carrier-envelope-phase (CEP) of few-cycle femtosecond laser pulses. The ability to characterize the CEP of few-cycle pulses is the backbone of attosecond metrology and key to achieving sub-cycle temporal resolution in a broad range of ultrafast laser applications. Unlike its predecessor, our new device does not require high vacuum or multichannel plates, which guarantees simple and user-friendly operation. MADEIRA supports center wavelengths ranging from the visible to the near-infrared domain, and operates at a repetition rate of up to 10 kHz.

MADEIRA relies on the detection of the light-induced, CEP-dependent current. The current is generated via strong-field ionization of gas-phase ethanol in the focus of the laser pulse and is probed by a pair of electrodes placed on either side of the focus.
The current flowing between the two electrodes is amplified and converted into a voltage output signal. A second output signal is obtained from a similar measurement of a phase-shifted copy of the pulse in a second focus. The CEP is retrieved from the two output signals, which can be acquired continuously without time limitation.