Dynamics during pulsed laser ablation of high T/sub c/ superconductor

Author

Nakamiya, T. ; Ikegami, T. ; Ebihara, K.

Author_Institution

Dept. of Electron. & Inf. Technol., Kyushu Tokai Univ., Kumamoto, Japan

Volume

3

Issue

1

fYear

1993

fDate

3/1/1993 12:00:00 AM

Firstpage

1057

Lastpage

1060

Abstract

The ablation of high critical temperature (T/sub c/) YBa/sub 2/Cu/sub 3/O/sub 7-x/ superconducting bulk (1-mm thickness) by a nanosecond-pulse KrF excimer laser ( lambda =248 nm) is studied numerically. The dynamics of ablation is simulated by solution of the one-dimensional heat flow equation. The finite-element method is applied to solve the equation, including the temperature dependence of the thermal conductivity of the bulk, the movement of a vapor-liquid interface, the latent heat of melting and ablation, and the energy of the laser-generated plume. The melting threshold energy density is found to be 0.08 J/cm/sup 2/, and the ablation threshold energy density is estimated to be 0.22 J/cm/sup 2/. The mean velocity of the laser-generated plume increases with the increase of laser energy density from 0.93*10/sup 4/ m/s (2 J/cm/sup 2/) to 1.95*10/sup 4/ m/s (10 J/cm/sup 2/).<>

Keywords

barium compounds; finite element analysis; heat of fusion; high-temperature superconductors; laser ablation; melting; pulsed laser deposition; superconducting thin films; thermal conductivity of solids; yttrium compounds; YBa/sub 2/Cu/sub 3/O/sub 7- delta /; ablation threshold energy density; dynamics; finite-element method; high T/sub c/ superconductor; high critical temperature; high temperature superconductors; laser-generated plume; latent heat; melting; melting threshold energy density; nanosecond-pulse KrF excimer laser; one-dimensional heat flow equation; pulsed laser ablation; temperature dependence; thermal conductivity; vapor-liquid interface; Atom lasers; Equations; High temperature superconductors; Laser ablation; Laser modes; Laser theory; Optical pulses; Pulsed laser deposition; Superconducting films; Thermal conductivity;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.233882

Filename

233882