Surface rippling on bulk metallic glass under nanosecond pulse laser ablation

Abstract

Molecular packing in highly stable glasses of vapor-deposited tris-naphthylbenzene isomers J. Chem. Phys. 136, 094505 (2012) Role of aluminum as an oxygen-scavenger in zirconium based bulk metallic glasses Appl. Phys. Lett. 100, 071909 (2012) Prediction of glass-forming ability and characterization of atomic structure of the Co-Ni-Zr metallic glasses by a proposed long range empirical potential J. Appl. Phys. 111, 033521 (2012) Structurally determined directionality identifies the boundary between mobile and immobile domains in a disordered material

Two-photon polarization-selective etching of emergent nano-structures on diamond surfaces

“…The rich variety of patterns produced as functions of facet and polarization reveal that the ejection probability is a complex function of the local surface structure and beam polarization. Such an ejection mechanism is consistent with the thresholdless and 'cold' nature of the process, and is distinct from the exponential and thermal nature of the periodic structuring observed previously [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] when using higher intensities, either near or above the ablation threshold. Further work is needed to determine whether bond scission results from direct coupling of the ultraviolet with carbon-carbon bonds or is reliant on cooperative processes with electronic states associated with surface reconstructions, radical sites or chemisorbed atoms.…”

“…The observed patterning has starkly contrasting properties to the laser-induced periodic surface structuring observed, to date, in any material [20][21][22][23][24][25][26][27] including diamond 20,[28][29][30][31] . For incident intensities near the ablation threshold or at the fringes of an ablation spot, ripple-like structures are produced with periodicity approximately equal to the wavelength of the incident light and with direction perpendicular to the laser polarization, except in a few special cases that combine angle of incidence and polarization to perturb the pattern symmetry 25,27 .…”

“…We found that the same grid structure and orientation were reproduced using circular polarization, which likewise projects an equal polarization along all lattice bonds. The pattern type and orientation is thus principally determined by the overlap between the polarization and directional surface states, rather than collective surface wave excitations of previous laserinduced patterns [20][21][22][23][24][25][26][27][28][29][30][31][32][33] . Our observations of structures with period less than 20 nm for small etch depths are consistent with a highly localized light-material interaction.…”

Cavitation bubble dynamics during pulsed laser ablation of a metallic glass in water

“…On the edge of the irradiated area, surface ripples can be clearly observed (see Fig. 2(a)), implying that significant thermo-hydrodynamic instabilities occurred due to the present water-confined laser ablation [13,16]. Fig.…”

“…This application has remarkably broadened the utilization of metallic glasses as advanced materials [11,12], and on the other hand, allows re-examining the traditional picture of laser-solid interaction [13][14][15]. It is noted that, however, laser ablation of metallic glasses was so far mostly performed in gaseous conditions, with only one exception [16].…”