M. Drobizhev et al., Photo-tautomer of Br-porphyrin: a new frequency-selective material for ultrafast time-space holographic storage, J LUMINESC, 86(3-4), 2000, pp. 391-397
We study spectral hole burning in the unstable tautomer form of free-base B
r-tetraethylporphyrin in poly(vinyl butyral) film, which is created by phot
o-transformation of the stable tautomer form at low temperature. We report
a Debye-Waller factor alpha = 0.7 at 4 K, burning quantum efficiency phi si
milar to 10(-3) and thermal stability up to 115 K for this system. We obser
ve for the first time that narrow-band illumination in the educt band leads
to the formation of vibronic holes in the photoproduct band. Because the o
scillator strength of the unstable form is at least one order of magnitude
larger than that of the stable form, this new material is well suited for r
ecording ultrafast time-and-space-domain holograms. Spectral hole burning w
ith femtosecond pulses was achieved. (C) 2000 Elsevier Science B.V. All rig
hts reserved.