The phonon Bragg switch: a proposal to generate sub-picosecond X-ray pulses

Abstract We discuss a method to modulate an X-ray beam that relies on the scattering of hard X-ray photons by a superlattice of optical phonons generated by ultrafast laser pulses incident on a Bragg crystal. Using commercially available laser systems and well-developed techniques for pulse shaping, the crystal lattice motion can be controlled so that efficient Bragg diffraction is switched on and off in a time comparable to a phonon oscillation period (typically, 0.1–1 ps). A detailed proposal is given for the case of GaAs.

[1]  Liu,et al.  Impulsive light scattering by coherent phonons in LaAlO3: Disorder and boundary effects. , 1995, Physical review letters.

[2]  R. Yen,et al.  Time-Resolved Reflectivity Measurements of Femtosecond-Optical-Pulse-Induced Phase Transitions in Silicon , 1983 .

[3]  Cho,et al.  Subpicosecond time-resolved coherent-phonon oscillations in GaAs. , 1990, Physical review letters.

[4]  Hiroshi Harima,et al.  Optical control of coherent optical phonons in bismuth films , 1996 .

[5]  Mazur,et al.  Ultrafast electronic disordering during femtosecond laser melting of GaAs. , 1991, Physical review letters.

[6]  Patrick Audebert,et al.  Femtosecond time-resolved X-ray diffraction from laser-heated organic films , 1997, Nature.

[7]  Manuel Cardona,et al.  Light Scattering in Solids , 2000 .

[8]  Merlin,et al.  Reversal of ferroelectric domains by ultrashort optical pulses. , 1994, Physical review letters.

[9]  Cheng,et al.  Theory for displacive excitation of coherent phonons. , 1992, Physical review. B, Condensed matter.

[10]  Glover,et al.  X-Ray Based Subpicosecond Electron Bunch Characterization Using 90 degrees Thomson Scattering. , 1996, Physical review letters.

[11]  K. Nelson,et al.  Time-resolved vibrational spectroscopy in the impulsive limit , 1994 .

[12]  Tom,et al.  Time-resolved study of laser-induced disorder of Si surfaces. , 1988, Physical review letters.

[13]  H. Cummins,et al.  Light scattering in solids , 1979 .

[14]  Roberto Merlin,et al.  Generating coherent THz phonons with light pulses , 1997 .

[15]  R. Yen,et al.  Femtosecond-Time-Resolved Surface Structural Dynamics of Optically Excited Silicon , 1983 .

[16]  D. Wiersma,et al.  ULTRAFAST PHENOMENA XI , 1998 .

[17]  Howard A. Padmore,et al.  Ultrafast structural changes measured by time-resolved X-ray diffraction , 1998 .

[18]  Raphael Tsu,et al.  Nonthermal pulsed laser annealing of Si; plasma annealing , 1979 .

[19]  Kwanpyo Kim,et al.  Femtosecond X-ray Pulses at 0.4 Å Generated by 90° Thomson Scattering: A Tool for Probing the Structural Dynamics of Materials , 1996, Science.