Epitaxial Ge2Sb2Te5 probed by single cycle THz pulses of coherent synchrotron radiation

  title={Epitaxial Ge2Sb2Te5 probed by single cycle THz pulses of coherent synchrotron radiation},
  author={Valeria Bragaglia and Alexander Schnegg and Raffaella Calarco and Karsten Holldack},
  journal={Applied Physics Letters},
A THz-probe spectroscopy scheme with laser-induced single cycle pulses of coherent synchrotron radiation is devised and adapted to reveal the dynamic THz transmittance response in epitaxially grown phase change materials upon 800 nm fs-laser excitation. Amorphous (a-) and crystalline (c-) films of the prototypical Ge2Sb2Te5 (GST) alloy are probed with single cycle THz pulses tuned to the spectral range of the highest absorption contrast at 2 THz. After an initial instantaneous sub-picosecond… 

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