%0 Journal Article %T Possible observation of parametrically amplified coherent phasons in K0.3MoO3 using time-resolved extreme-ultraviolet ARPES %A H. Y. Liu %A I. Gierz %A J. C. Petersen %A S. Kaiser %A A. Simoncig %A A. L. Cavalieri %A C. Cacho %A I. C. E. Turcu %A E. Springate %A F. Frassetto %A L. Poletto %A S. S. Dhesi %A Z. -A. Xu %A T. Cuk %A R. Merlin %A A. Cavalleri %J Physics %D 2012 %I arXiv %R 10.1103/PhysRevB.88.045104 %X We use time- and angle-resolved photoemission spectroscopy (tr-ARPES) in the Extreme Ultraviolet (EUV) to measure the time- and momentum-dependent electronic structure of photo-excited K0.3MoO3. Prompt depletion of the Charge Density Wave (CDW) condensate launches coherent oscillations of the amplitude mode, observed as a 1.7-THz-frequency modulation of the bonding band position. In contrast, the anti-bonding band oscillates at about half this frequency. We attribute these oscillations to coherent excitation of phasons via parametric amplification of phase fluctuations. %U http://arxiv.org/abs/1206.5743v3