Optical melting of the transverse Josephson plasmon: A comparison between bilayer and trilayer cuprates
Physical Review B American Physical Society (APS) 95:10 (2017) 104508
Dynamical Stability Limit for the Charge Density Wave in K_{0.3}MoO_{3}.
Physical review letters 118:11 (2017) 116402
Abstract:
We study the response of the one-dimensional charge density wave in K_{0.3}MoO_{3} to different types of excitation with femtosecond optical pulses. We compare direct excitation of the lattice at midinfrared frequencies with injection of quasiparticles across the low energy charge density wave gap and with charge transfer excitation in the near infrared. For all three cases, we observe a fluence threshold above which the amplitude-mode oscillation frequency is softened and the mode becomes increasingly damped. We show that all the data can be collapsed onto a universal curve in which the melting of the charge density wave occurs abruptly at a critical lattice excursion. These data highlight the existence of a universal stability limit for a charge density wave, reminiscent of the Lindemann criterion for the melting of a crystal lattice.Narrowband carrier-envelope phase stable mid-infrared pulses at wavelengths beyond 10 μm by chirped-pulse difference frequency generation.
Optics letters 42:4 (2017) 663-666
Abstract:
We report on the generation of narrowband carrier-envelope phase stable mid-infrared (MIR) pulses between 10 and 15 μm. High pulse energies and narrow bandwidths are required for the selective nonlinear excitation of collective modes of matter that is not possible with current sources. We demonstrate bandwidths of <2% at 12.5 μm wavelength through difference frequency generation between two near-infrared (NIR) pulses, which are linearly chirped. We obtain a reduction in bandwidth by one order of magnitude, compared to schemes that make use of transform-limited NIR pulses. The wavelength of the narrowband MIR pulse can be tuned by changing the optical delay between the two chirped NIR pulses.Enhanced electron-phonon coupling in graphene with periodically distorted lattice
Physical Review B American Physical Society (APS) 95:2 (2017) 024304
Generation of narrowband, high-intensity, carrier-envelope phase-stable pulses tunable between 4 and 18 THz.
Optics letters 42:1 (2017) 129-131