Spectroscopic analysis of electronically excited species in XeCl excimer laser-induced plasmas from the ablated high-temperature superconductor YBa2Cu3O7

Abstract

Optical spectroscopic analyses have been performed to study luminescence from plasmas produced by ablation of YBa2Cu3O7 single-phase high Tc bulk superconductors exposed to XeCl excimer laser (308 nm) pulses. Only excited atomic neutral and single ionized species (Cu/Cu+, Ba/Ba+, Y/Y+) were observed within the experimental resolution of an optical multichannel analyzer detection system, when irradiating the targets in vacuum (∼10−5–10−4 Torr). Conspicuously absent in the spectra (300–800 nm range) are molecular emission bands that would appear if large excited molecules or fragments were present. Implications of the present results are discussed which relate to an early hypothesis about the laser ablation mechanism and their influence on high Tc film characteristics.

Electronic State Distributions of YBa2Cu3O7-x Laser-Ablated Plumes

“…Collected spectra has consistently identified yttrium and barium neutrals and ions, and copper neutrals. [10,19,27,39,88,90,91] However, there is disagreement with detection of copper ion emission, with some authors reporting ion emission is not present [27,39,91], while at least one group reported copper ion emission. [10] Also of significant interest is the formation and detection of oxides in the plume.…”

“…[9] Early papers in the literature on the topic of electronic state distributions tended to take simple approaches using sparse data sets, and presented limited detail. An example of this approach is seen in Dyer [27], which reported an electronic temperature for the plume based upon the intensity ratio of two yttrium ion lines in a narrow A similar approach to Dyer was taken by Auciello [10], where spectra was collected over the 320 -830 nm wavelength range. Thirty unambiguous emission lines were assigned to specific transitions.…”

“…[9] Another line-ratio measurement was conducted by Harilal [91] With the exception of Ying's paper, [91] most of the published electronic temperature measurements have been obtained using line-ratio measurements. [8,10,[27][28][29]45] There is a risk to performing a calculation based on a ratio of two data points, in that a perturbation to one of the data points may skew the results more than if the calculation was performed by fitting a line through a greater number of data points. Several mechanisms may cause a significant error in a data point, resulting in a skewed result.…”

Langmuir probe measurements and mass spectrometry of plasma plumes generated by laser ablation of La0.4Ca0.6MnO3

“…[1][2][3] The evaporated plasma plume contains ionized atoms and molecules, neutrals and electrons, and the kinetics of the plasma plume will have a direct influence on the structural and physical properties of a deposited film. To better understand these plasma properties, a range of plasma analytical techniques such as Langmuir probe, 4-10 plasma imaging, [11][12][13][14] emission spectroscopy, [15][16][17][18][19][20] and mass spectrometry [21][22][23][24][25][26] have been used also in a number of combinations to cover different aspects and properties of plasma species. 27,28 For example, Geohegan and Puretzky investigated the laser ablation plume thermalization dynamics in background gases thereby combining optical absorption and emission spectroscopy, imaging and ion probe analysis.…”

Time evolution of the electron density and temperature in laser-produced plasmas from YBa2Cu3O7

“…The emission spectra obtained from a multicomponent YBa 2 Cu 3 O 7 target show numerous emission lines and bands corresponding to neutral particles, ions and diatomic molecules. The dynamics of the laser-ablated YBa 2 Cu 3 O 7 plume has been studied by various techniques such as optical emission spectroscopy [5][6][7][8][9], streak photography [10,11], optical absorption spectroscopy [12][13][14], * Present Address: Department of Physics, Sree Narayana College, Punalur 691 305, India * * E-mail: root@cochin.ernet.in optical time-of-flight measurements in the nanosecond timescale range [15][16][17][18][19], interferometry [20], and laser-induced fluorescence [21]. However, most of them have been aimed at identification of ablated species and on the evaluation of their velocity distributions.…”