Conditions for femtosecond laser melting of silicon

Korfiatis, D. P.; Thoma, K-A Th; Vardaxoglou, J.C.

doi:10.1088/0022-3727/40/21/047

Cited by 63 publications

(44 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3. Our estimation of the damage threshold for the given wavelength and pulse duration of the pump turns out to be in line with previous measurements using different pump pulses, as shown in the lower plot where the present estimate (fluence threshold F th~0 .03 J/cm 2 ) for the irreversible damage is compared with various calculated (open symbols) and experimental (filled symbols) results (see [10] and Ref. therein).…”

Section: Experimental Results: Ultrafast Melting Of Si(100)supporting

confidence: 90%

See 1 more Smart Citation

Probing phase transitions under extreme conditions by ultrafast techniques: Advances at the Fermi@Elettra free-electron-laser facility

Cicco

D’Amico

Zgrablić

et al. 2011

Journal of Non-Crystalline Solids

View full text Add to dashboard Cite

Section: Experimental Results: Ultrafast Melting Of Si(100)supporting

confidence: 90%

“…[7] for a review on semiconductors). For example, melting of crystalline silicon has been studied since the early times of ultrafast optical spectroscopy (see [8][9][10] and Ref. therein), while melting, crystallization and re-amorphization were studied for various amorphous semiconductors [11,12].…”

Section: Introductionmentioning

confidence: 99%

Probing phase transitions under extreme conditions by ultrafast techniques: Advances at the Fermi@Elettra free-electron-laser facility

Cicco

D’Amico

Zgrablić

et al. 2011

Journal of Non-Crystalline Solids

View full text Add to dashboard Cite

“…Silicon is a widely studied material in the context of strongly driven phase transitions, both experimentally [1][2][3][4][5][6] and theoretically [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29], where it is found to melt on a subpicosecond timescale at high excitations. Most theoretical studies of nonthermal melting in silicon have employed ab initio simulation methods.…”

Section: Introductionmentioning

confidence: 99%

Simulating electronically driven structural changes in silicon with two-temperature molecular dynamics

Darkins

Murphy

et al. 2018

Phys. Rev. B

View full text Add to dashboard Cite

Radiation can drive the electrons in a material out of thermal equilibrium with the nuclei, producing hot, transient electronic states that modify the interatomic potential energy surface. We present a rigorous formulation of two-temperature molecular dynamics that can accommodate these electronic effects in the form of electronic-temperature-dependent force fields. Such a force field is presented for silicon, which has been constructed to reproduce the ab initio-derived thermodynamics of the diamond phase for electronic temperatures up to 2.5 eV, as well as the structural dynamics observed experimentally under nonequilibrium conditions in the femtosecond regime. This includes nonthermal melting on a subpicosecond timescale to a liquidlike state for electronic temperatures above ∼1 eV. The methods presented in this paper lay a rigorous foundation for the large-scale atomistic modeling of electronically driven structural dynamics with potential applications spanning the entire domain of radiation damage.

show abstract

“…Thus, it can be surprising how well "thermal" models could sometimes reproduce experimental observations of phase transitions triggered by laser pulse irradiation of solids [10][11][12][13]. This controversy stimulated intense discussions [14,15].…”

Section: Introductionmentioning

confidence: 99%

“…It is generally believed that for a low deposited dose, thermal melting of a semiconductor or an insulator can be induced, while for a higher dose, when typically ∼10% of the valence-band electrons are excited to the conduction * nikita.medvedev@desy.de band [6,10], a nonthermal melting occurs. This is, however, not always the case: diamond is a counterexample.…”

Section: Introductionmentioning

confidence: 99%

Thermal and nonthermal melting of silicon under femtosecond x-ray irradiation

2015

View full text Add to dashboard Cite

As is known from visible-light experiments, silicon under femtosecond pulse irradiation can undergo so-called "nonthermal melting" if the density of electrons excited from the valence to the conduction band overcomes a certain critical value. Such ultrafast transition is induced by strong changes in the atomic potential energy surface, which trigger atomic relocation. However, heating of a material due to the electron-phonon coupling can also lead to a phase transition, called "thermal melting." This thermal melting can occur even if the excited-electron density is much too low to induce nonthermal effects. To study phase transitions, and in particular, the interplay of the thermal and nonthermal effects in silicon under a femtosecond x-ray irradiation, we propose their unified treatment by going beyond the Born-Oppenheimer approximation within our hybrid model based on tight-binding molecular dynamics. With our extended model we identify damage thresholds for various phase transitions in irradiated silicon. We show that electron-phonon coupling triggers the phase transition of solid silicon into a low-density liquid phase if the energy deposited into the sample is above ∼0.65 eV per atom. For the deposited doses of over ∼0.9 eV per atom, solid silicon undergoes a phase transition into high-density liquid phase triggered by an interplay between electron-phonon heating and nonthermal effects. These thresholds are much lower than those predicted with the Born-Oppenheimer approximation (∼2.1 eV/atom), and indicate a significant contribution of electron-phonon coupling to the relaxation of the laser-excited silicon. We expect that these results will stimulate dedicated experimental studies, unveiling in detail various paths of structural relaxation within laser-irradiated silicon.

show abstract

Conditions for femtosecond laser melting of silicon

Cited by 63 publications

References 45 publications

Probing phase transitions under extreme conditions by ultrafast techniques: Advances at the Fermi@Elettra free-electron-laser facility

Probing phase transitions under extreme conditions by ultrafast techniques: Advances at the Fermi@Elettra free-electron-laser facility

Simulating electronically driven structural changes in silicon with two-temperature molecular dynamics

Thermal and nonthermal melting of silicon under femtosecond x-ray irradiation

Contact Info

Product

Resources

About