Skip to main content Accessibility help
×
Hostname: page-component-848d4c4894-89wxm Total loading time: 0 Render date: 2024-07-06T07:48:19.874Z Has data issue: false hasContentIssue false

6 - Doubly Charged Ions Formation from the Multiphoton Atomic Ionization of Alkaline Earth Metals

Published online by Cambridge University Press:  13 July 2022

Man Mohan
Affiliation:
Emeritus Professor, Department of Physics and Astrophysics, University of Delhi, Delhi
Anil Kumar Maini
Affiliation:
Former Director, Laser Science and Technology Centre, Delhi
Aranya B. Bhattacherjee
Affiliation:
Associate Professor, Department of Physics, ARSD College, University of Delhi, Delhi
Get access

Summary

Introduction

The creation of doubly charged ions upon the multiphoton ionization of atoms and molecules was observed for the first time in[1]. Discovery of the effect of the creation of doubly charged ions upon multiphoton atomic ionization laid the foundation of a new branch in the physics of nonlinear ionization processes that involved the creation of multicharged ions due to the multiphoton or tunneling ionization of atoms and molecules.

In later experiments, the creation of doubly charged ions was revealed in experiments with atomic barium, samarium, europium, and ytterbium[2−4]. The creation of doubly charged ions was also observed upon multiphoton ionization of inert gas atoms and other atoms and molecules[5]. Experimental results have demonstrated the general character of the creation of doubly charged ions upon multiphoton ionization of various groups of atoms.

In this chapter, we will discuss the creation of singly and doubly charged ions upon multiphoton atomic ionization of alkaline-earth elements using laser radiation with nanosecond pulse duration at laser field strengths ϵ = 5 x 106 − 109 V/cm, which are significantly less than the intra-atomic field ϵa = 5x109 V/cm. The results of using this field strength significantly differ from the recent results obtained at the laser field strength ϵ ˂ 5 x 109 V/cm or ϵ > 5 x 109 V/cm in experiments with femtoseconds and atto second laser pulses[6]. The differences include the domination of the tunneling ionization of atoms and molecules under such conditions and the creation of doubly charged ions. The main processes are electron rescattering, shaking, etc.[6].

The processes that lead to the creation of doubly charged ions upon multiphoton ionization of the alkaline-earth elements under the given conditions differ from the above processes. Two effects (cascade and two-electron)were proposed in[7, 8] to account for the creation of doubly charged ions upon the multiphoton ionization of alkaline-earth elements. In the cascade effect, doubly charged ions (A2+) are created owing to themultiphoton ionization of singly charged ions (A+) that appear in the presence of the same laser pulse due to themultiphoton ionization of atoms A : A+K0 ħω−A++ e and A+ +K1 ħω−A2+ +e.

Type
Chapter
Information
Publisher: Foundation Books
Print publication year: 2014

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Save book to Kindle

To save this book to your Kindle, first ensure coreplatform@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×