12. Laser Ablation in Optical Components and thin Films

Reichling, Michael

doi:10.1016/s0076-695x(08)60404-4

Cited by 4 publications

(4 citation statements)

References 124 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Surface defects and adsorbed species induce local electronic states in the insulator band gap, initiating optical absorption. The absorbed energy is transferred to the lattice and may cause damage and ablation, especially when dealing with high-power laser light [1]. Information about the atomic and electronic structure of particular surface defects can be very helpful for achieving a detailed 3 Author to whom any correspondence should be addressed.…”

Section: Introductionmentioning

confidence: 99%

Theoretical modelling of steps on the CaF₂(111) surface

Puchin

Puchina

Huisinga

et al. 2001

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The atomic and electronic structure and relaxation of the perfect (111) surface and several low-index surfaces of CaF2 are calculated using an ab initio Hartree-Fock method. We find marked differences between the bulk and surface valence band structures; however, the band gap is reduced by only 0.5 eV for the stepped surface. The (111) surface is found to exhibit no significant relaxation and we obtain a surface energy of 0.47 J m-2. The atomic structure of two types of stepped surface both having 0.32 nm high steps aligned along the [110] crystallographic direction is determined and the step energies are found to be 0.25 and 0.35 nJ m-1, respectively. Step energies for configurations involving other orientations of steps are considerably higher. The formation of double-height steps along [110], however, is found to be energetically favourable. A considerable amount of relaxation is found for stepped surfaces and we explain qualitatively why it results in a roughening of the surface in some cases. The energetic position of gap electronic states induced by steps on the (111) surface is found to be very similar to that for surface states of the perfect (111) surface; i.e. such states do not yield a significant density of states more than 0.5 eV above the bulk valence band maximum. We discuss how the step formation energies found here might explain surface topographical features found on cleaved and grown CaF2(111) surfaces.

show abstract

Section: Introductionmentioning

confidence: 99%

Theoretical modelling of steps on the CaF₂(111) surface

Puchin

Puchina

Huisinga

et al. 2001

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…It is clearly visible that the periodic nanostructures observed in the XUV-CDL irradiation experiment differ from the morphology of all the damage patterns observed on alkali-earth-halide surfaces exposed to radiation of various kinds in numerous studies reported earlier [26][27][28][29][30][31][32][33][34][35][36][37][38][39]. We should keep in mind that an attenuation length of 46.9-nm XUV-CDL radiation in BaF 2 is very short, i.e., only about 10 nm [40,41].…”

Section: Discussion and Outlookmentioning

confidence: 90%

“…This contrasts with our finding, where it is the orientation of crystallographic planes which is related to the grating-vector direction. It seems that the crystallographic planes played an important role in the damage to CaF2 induced by nanosecond pulses of UV laser radiation [30,31]. The damage pattern shows linear edges oriented along the crystallographic planes.…”

Section: Discussion and Outlookmentioning

confidence: 99%

Characterizing the Grating-like Nanostructures Formed on BaF2 Surfaces Exposed to Extreme Ultraviolet Laser Radiation

et al. 2022

View full text Add to dashboard Cite

Monocrystalline barium fluoride (BaF2) slab targets were irradiated by focused 46.9-nm laser radiation at various fluence levels above the ablation threshold. Well-developed ablation patterns with sharp edges were studied by AFM (atomic force microscopy). Their inner surfaces were uniformly covered by periodic structures. The spatial period of the ripples depends on the laser fluence. When the sample is rotated by 45°, the orientation of the grating-like structure changes accordingly. Thus, the grating vector of the periodic structure seems to be coupled to the crystallographic planes of the single crystal. This means that the XUV-laser induced ripples reported here differ from LIPSS (laser-induced periodic surface structures) associated with interference phenomena occurring on illuminated surfaces. Therefore, other mechanisms are discussed to explain the formation of the periodic nanostructures reported in this article.

show abstract

“…The incident light is absorbed by electronic transitions in the solid. In a metal or semiconductor the light produces excited electrons which subsequently interact with the atoms [2] . At sufficiently high intensities, "seed" electrons from impurities or multiphoton processes act as "absorbers" by inverse bremsstrahlung processes for the avalanche processes, which eventually can lead to an optical breakdown.…”

Section: Introductionmentioning

confidence: 99%

Characteristics of Ions Emitted from Laser-Induced Silver Plasma

Rafique

Khaleeq-ur-Rahman

Munazza

et al. 2008

Plasma Sci. Technol.

View full text Add to dashboard Cite

In this work, study of laser-induced ions is presented. The plasma was produced by focusing a Nd:YAG laser, with a wavelength of 1064 nm, a pulsed width of 9∼14 ns, a power of 1.1 MW and energy of 10 mJ, on silver target in vacuum (10 −3 Torr = 1.3332 Pa). The characteristics of ion streams were investigated by CR-39 detectors located at angles of 0 o , 30 o , 60 o and 90 o with respect to normal of the target. The distance between the silver target and each detector was 11 cm. The energy of silver ions was found ranging from 1.5 eV to 1.06E4 eV. There was a high concentration of ions with low energy as compared to those with high energy, showing the energy distribution amongst the ions. The flux of ions was maximum in the axial direction which was decreasing with the angle increase with respect to normal of the target, and finally became minimum in the radial direction. Hence the silver ions have shown anisotropic behaviour.

show abstract

12. Laser Ablation in Optical Components and thin Films

Cited by 4 publications

References 124 publications

Theoretical modelling of steps on the CaF₂(111) surface

Theoretical modelling of steps on the CaF₂(111) surface

Characterizing the Grating-like Nanostructures Formed on BaF2 Surfaces Exposed to Extreme Ultraviolet Laser Radiation

Characteristics of Ions Emitted from Laser-Induced Silver Plasma

Contact Info

Product

Resources

About

12. Laser Ablation in Optical Components and thin Films

Cited by 4 publications

References 124 publications

Theoretical modelling of steps on the CaF2(111) surface

Theoretical modelling of steps on the CaF2(111) surface

Characterizing the Grating-like Nanostructures Formed on BaF2 Surfaces Exposed to Extreme Ultraviolet Laser Radiation

Characteristics of Ions Emitted from Laser-Induced Silver Plasma

Contact Info

Product

Resources

About

Theoretical modelling of steps on the CaF₂(111) surface

Theoretical modelling of steps on the CaF₂(111) surface