Laser based acceleration of charged particles

• Author / Creator

  Popov, Konstantin

• In this Thesis, two problems were studied: a direct vacuum acceleration of electrons by a tightly focused ultrashort relativistic laser pulse and ion acceleration in the process of spherical laser-heated plasma explosion. The electromagnetic field of a tightly focused laser pulse was evaluated numerically by means of Stratton-Chu integrals. The properties of the focused field were analyzed in detail for a plane wave or a macroscopically large Gaussian beam incident onto the mirror. Free electrons moving in the tightly focused field were found to accelerate by two possible mechanisms: focal spot acceleration and capture-and-acceleration scenario. The two mechanisms were studied in detail. Comparison of the mirror-focused field with first- and fifth-order paraxial fields is performed. A 3D electromagnetic PIC code SCPIC was created for simulations of pulse interaction with targets having a finite number of particles interacting with each other by collective fields. Atto-second bunch formation was observed in the interaction with ultra-small or ultra-thin targets. Physical mechanism of bunch formation is explained. The problem of electrostatic explosion of a nano-scale spherical plasma with initially hot electrons and cold ions was solved numerically. Expansion in a wide regime of electron temperature $0 < T \leq \infty$ was studied in detail for different initial density profiles of plasma. Favorable conditions for obtaining mono-energetic ions resulting from the explosion were specified in single and two ionic species cases. In case of a two-species explosion, the number of mono-energetic, $\delta\varepsilon/\varepsilon < 10\%$, ions can be as high as 70-80\% of the total light ions for a wide range of electron temperatures.

• Subjects / Keywords

  • Charged particle dynamics; tightly focused laser; short laser pulses; ultrahigh intensity interactions; nano-scale targets; direct vacuum acceleration; Coulomb explosion; monoenergetic electrons; monoenergetic ions

• Graduation date

  Fall 2009

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3Z892R9R

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.