Visible Light Emission in Highly Charged Kr¹⁷⁺Ions Colliding with an Al Surface

Abstract

We report light emission during the bombardment of Kr 17+ ions on an Al surface in the wavelength range 300-700 nm. The three spectral lines of the sputtered Al atoms belong to transitions of Al I 3𝑝 2 𝑃 o 3/2 -3𝑑 2 𝐷 5/2 at 309.26, Al I 3𝑝 2 𝑃 o 1/2 -4𝑠 2 𝑆 1/2 at 394.72 and Al I 3𝑝 2 𝑃 o 3/2 -4𝑠 2 𝑆 1/2 at 396.50 nm. During the neutralization process, the seven spectral lines of Kr I and Kr II from the incident ion of Kr 17+ attribute to transitions of Kr I 5𝑝 2 [3/2]2-7𝑑 2 [1/2] o 1 at 616.33, Kr II 5𝑠 2 𝐷 5/2 -5𝑝 2 𝐷 o 3/2 at 410.86, Kr II 5𝑝 4 𝑃 o 5/2 -6𝑠 4 𝑃 5/2 at 430.58, Kr II 4𝑑 2 𝐷 3/2 -4𝑓 2 [3] o 5/2 at 434.42, Kr II 4𝑑 4 𝐷 1/2 -5𝑝 2 𝑆 o 1/2 at 485.80, Kr II 4𝑝 4 𝑆 3/2 -6𝑠 4 𝑃 o 3/2 at 618.57 and Kr II 5𝑝 4 𝑃 o 3/2 -4𝑑 2 𝐷 5/2 at 656.41 nm. Light emissions of sputtered species depend on energy of the incident ions deposited on the target surface atoms. Light emissions of the neutralized projectiles are formed due to many electrons of the conduction band of the solid surface captured in excited states of the incident ion.