Real-time measurement of picosecond THz pulses by an ultra-fast YBa2Cu3O7−d detection system

Abstract

The temporal evolution of picosecond THz pulses generated at ANKA, the electron storage ring of the Karlsruhe Institute of Technology, has been measured in real-time using an ultra-fast YBa2Cu3O7−δ detection system. YBa2Cu3O7−δ thin-film detectors with 30 nm thickness were patterned to microbridges (2 μm long, 4.5 μm wide) and embedded into a planar log-spiral THz antenna. The detectors were glued on a silicon lens and installed in an ultra-fast readout system with a temporal resolution of 15 ps (full width at half maximum). Detector responses as short as 17 ps were recorded showing very good agreement with the expected storage ring bunch lengths.

Highly Responsive Y–Ba–Cu–O Thin Film THz Detectors With Picosecond Time Resolution

“…The detection of CSR THz pulses at the electron storage ring ANKA has already been demonstrated [15], [27]. The filling patterns of the storage ring with three consecutive trains as well as single pulses were successfully monitored.…”

“…The filling patterns of the storage ring with three consecutive trains as well as single pulses were successfully monitored. Single pulses as short as 6.8 ps (root mean square) were recorded [15].…”

“…Response times of only a few picoseconds were measured from optical to infrared wavelengths using pump-probe and autocorrelation techniques [11] - [14]. We recently demonstrated picosecond response times in the THz frequency range [15]. Furthermore, a dynamic range larger than 30 dB was found [16].…”

Microbunching Instability in Relativistic Electron Bunches: Direct Observations of the Microstructures Using Ultrafast YBCO Detectors

“…In this Letter, we demonstrate the possibility to monitor the microstructure dynamics in real time (turn-by-turn), when the electron bunch duration exceeds several tens of picoseconds, using a new generation of ultrafast detectors based on thin films of the high-temperature superconductor YBa 2 Cu 3 O 7−x (YBCO) [12][13][14]. Indeed, the temporal resolution of these detectors is only limited by the bandwidth of readout electronics and oscilloscope speed (16 ps FWHM here), and thus allows us to record details of the emitted CSR pulses.…”

“…At the output port of the BL6B THz beam line [16,17], we placed the thin-film YBCO detector, described in detail in Refs. [12][13][14]. It was operated at liquid nitrogen temperature without any bias.…”