Photoinitiated dynamics studied in the femto- to nanosecond time and the

terahertz to petahertz frequency domain: PIDID a multi-institutional initiative

Organigram PIDID collaboration

The PIDID project will substantially improve the experimental opportunities for accelerator based time-resolved measurements in Germany. The proposed development of the experimental infra-structures at FELBE and FLASH will establish a complementary instrumentation that allows the contributing groups for the first time to perform their research in an unprecedented combination of fs – ns time- and THz – PHz frequency domain. The close collaboration of German and Russian partners will carry out the development which will master solutions to the problems that presently inhibit a routine user program at the two facilities.

At the heart of this proposal is the fundamental finding that understanding of the fs – ns dynamics of photoinitiated and phonoinitiated dynamics in materials requires a combination of techniques and light pulse properties only available from accelerator based photon sources, while at the same time the available instrumentation at the two German 4th generation photon facilities FLASH and FELBE is in its present state not yet prepared to adequately fulfill the needs of the growing user communities.












  • 02/2011, postdoc at FUB/HZDR starts work (WP3)
  • 09/2011 postdoc at DESY starts work (WP4)
  • 12/2011 first (pilot) users from U Niemegen, FHI and HZDR at the ps - kHz pump probe beamline at FELBE Erste Nutzer an der neuen ps - KHz beamline
  • 16.12.2011 - Kick Off workshop @ DESY/talks: FLASH overview, FELBE/TELBE overview, Status WP2, Status WP3, Status WP4, Status WP5
  • 01/2012 laser tables for new THz photondiagnostic station at FLASH installed new THz photondiagnostic station at FLASH
  • 16.03./17.03.2012 FTIR measurements at THz beamline @ FLASHHZDR FT-IR @ FLASH THz beamline
  • 04/2012 new beamline OL-03 implemented at FT-IR spectrometer @ HZDRFT-IR  @ OL3 HZDR
  • 11/2012: beamtime for investigation of photosensitive protein dynamics and water under selective vibrational excitation at the THz FEL FELBEProtein Messzeit FELBE
  • 11/2012: THz pump X-ray probe beamtime @ FLASH with DESY and the MPI HeidelbergTHz beamtime @ FLASH 11/2012
  • 10.02.2012 - 17.12.2012: THz pump X-ray probe / Magnetization dynamics experiment @ FLASH (collaboration with university of Niemwegen, HZB, DESY and FHI)THz pump X-ray probe @ FLASH: magnetization dynamics




Collaborative measurements:

  • Using the Vertex 80v FTIR spectrometer at the HZDR, transmission characteristics of different THz filters, materials  can be measured if requested by the partners of the PIDID collaboration.

PIDID collaborative measurements

  • 08/2011: Pilotstepscanexperiments at the FUB (WP2)
  • 07/2011: THz pump X-ray probe beamtime at FLASH (WP2, WP4)
  • 04/2011: THz pump X-ray probe beamtime at FLASH (WP2, WP4)



WP1 “Subwavelength Resolution”:

At FELBE, a set up for performing time-resolved and nanoscale microscopy and spectroscopy at low temperatures (WP1) will be developed. This instrument uniquely allows not only to investigate and image our samples of interest over the whole spectral range of the FELBE beamline with a sub-wavelength resolution (of a few 10 nm), but equally provides spectral fingerprints of individual molecules (proteins, charge-transfer molecules, polymers), Q-dots, or local dopants in semiconductor nanostructures and oxides, even for nanoscale buried structures. Of interest here is also the time-dependent decay of molecular and atomic excitations; this clearly shows the need and benefit of all the developments done within this project. The collaborations within the consortium therefore are very intense, covering THz issues with WP2, development of single-pulse detection for the nanoscale

inspection in WP5, time-resolved IR spectroscopy and 3D-mapping of IR bands (WP3) on selected samples (biological, oxides, etc.), as well as complementary macroscopic (WP4) and nanoscopic investigations (WP1) between FLASH and FELBE.

WP2 “ps beamline”:


At FELBE a ps beamline (WP2) shall be implemented, providing narrow bandwidth THz pulses (0.4 – 2% FWHM), tunable in a spectral range between 66 and 1.2 THz and with pulse energies in the µJ regime as well as an adjustable repetition rate between 1 and 100 kHz to allow THz pump THz/VIS/ UV probe experiments on semiconductors, semiconductor nanostructures and complex oxides. This workpackage is lead by the HZDR although the required development of single-shot THz photon diagnostic and slicing of the MHz THz pulse trains is performed in close collaborations with DESY, UHH, TUB, UDE, TUKL, Budker Institute, LITP.

WP3 “Timeresolved IR spectroscopy on proteins:

This beamline shall be combined with an endstation for time-resolved IR spectroscopy on proteins (WP3) consisting of a step-scan FT-IR difference spectroscopy set up with µs time resolution as well as a nonlinear optical set up for the ps time domain to allow for novel three-color UV-VIS/THz pump/ IR difference spectroscopy probe experiments with the tunable narrow band width THz pulses as selective pump for low energy excitations. This project is lead by the FUB who will transfer its expertise in the instrumentation development for time-resolved IR difference spectroscopy to FELBE and is collaborating with partners from HZDR, DESY, UDE, TUKL, Budker institute, LITP to develop an endstation for routine three-color user experiments with THz pump pulses tunable in the frequency

range of 1.2 THz - 66 THz, UV-VIS pump pulses in a wavelength range of 300-700 nm and spectrally broad probe radiation in a frequency range between 1.2 - 66 THz.

time resolved IR spectroscopy

The issue of different penetration depth of the Vis, THz and MIR radiation involved in the pilot experiment is overcome by a novel ATR (attenuated total reflection) set up, where the two pump beams, THz tunable between 1.2 and 66 THz from the FEL and 532 nm radiation from a table-top frequency-doubled Nd:YAG laser system irradiate the protein film from the top while the broadband infrared radiation from the globar source of the FT-IR spectrometer is probing the IR absorption by attenuated total reflection from inside the ATR prism.

pump probe scheme

WP4 “fs beamline”:

At FLASH implementation of the fs beamline (WP4) will provide instrumentation for truly synchronized fs pump probe experiments from soft X-rays to THz. More precisely, it will provide three tunable laser sources, one in the soft X-ray, one in the VIS/NIR and one in the THz spectral range. These lasers are mutually synchronized down to few 10s of fs. In addition this workpackage will provide control over the repetition rate of the THz pulses from 1Hz – 500 kHz within the FLASH burst. This tool will also provide control over the temporal pulse structure and its spectral bandwidth. This achievements will enable a novel class of experiments such as vibrational control of complex materials, which were impaired by limited FLASH capabilities. The required development of single-shot THz photon diagnostic and slicing of the MHz THz pulse train is performed in close collaborations with DESY, UHH, UDE, TUKL, TUB, Budker institute, and LITP.


WP5 “Development of single pulse detector”:

Finally, to provide for the required single-pulse photon diagnostic and alignment of the temporal overlap, the TUB is leading the task for the development of single-pulse detectors (WP5) to be used at FLASH and FELBE and collaborating with partners from DESY, HZDR and the Budker institute. The TUB is furthermore the German contact of the Budker Institute in the development of an ultra broadband (THz – UV) imaging detector system based on a microbolometer array.