Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser...
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Transcript of Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser...
![Page 1: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/1.jpg)
Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser
Radiation
Ryan DuToitXiaoxu Guan (Mentor)
Klaus Bartschat (Mentor)
![Page 2: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/2.jpg)
Overview
• Motivation– Intense and ultrashort light pulses have opened up
new avenues to trace and steer electronic motion in atomic and molecular systems (atomic-scale electron dynamics).
– Generalize previous results to elliptical polarization
![Page 3: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/3.jpg)
Overview
• Theoretical Formulation– Discretization of system using prolate spheroidal
coordinates– Solve time dependent Schrödinger Equation
(complicated partial differential equation)
![Page 4: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/4.jpg)
Overview
• Results– Survival probability: orientation dependence– Angular distribution of photoelectron
• Outlook and Future Work
![Page 5: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/5.jpg)
Introduction to Simulation
• Simulate short laser pulse acting on a H2+ ion
• 1018 attoseconds = 1 second
• More attoseconds in one second than there are seconds in the age of the universe!
• The electric field interacts with the electron, which is what we are interested in.
![Page 6: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/6.jpg)
Prolate Spheroidal Coordinate System
![Page 7: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/7.jpg)
Electric Field
Linear Polarization Elliptical Polarization
![Page 8: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/8.jpg)
![Page 9: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/9.jpg)
Electric Field
![Page 10: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/10.jpg)
Theoretical Foundation
• Need to solve the time dependent Schrödinger Equation for the electron:
• Using time propagation, solution is:
![Page 11: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/11.jpg)
Theoretical Foundation
• Exponential of large matrix is a MASSIVE computational task
• Finite-Element Discrete-Variable Representation (FE-DVR)– Divide space into separate elements– Expand wavefunction into basis of Lagrange polynomials– Use Gaussian quadrature to approximate integrals
• Transform H into a smaller h matrix– Short iterative Lanczos algorithm
![Page 12: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/12.jpg)
![Page 13: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/13.jpg)
Solving Wavefunction
• After expanding into basis:
• Matrix h is orders of magnitude smaller than H– Rank of H ≈ 200,000– Rank of h ≈ 15
• Diagonalization goes like• This is an approximation
![Page 14: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/14.jpg)
Execution
• Code written in FORTRAN
• Use MPI for parallel programming
• Job runs on cluster here at Drake– 8 processors, 8 cores per processer = 64 threads
• Entire run takes 2-6 hours
![Page 15: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/15.jpg)
Theoretical Foundation
• Once we have wave function of electron, we extract physical information via operators.
• Survival Probability
• Angular distribution of photoelectron
![Page 16: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/16.jpg)
![Page 17: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/17.jpg)
What is angular distribution?
• Probability of electron being ejected at a given angle
• Quantum effects easy to see
![Page 18: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/18.jpg)
Parallel Electric Field
40 eV 70 eV 150 eV
200 eV 250 eV 300 eV
![Page 19: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/19.jpg)
Perpendicular Electric Field
40 eV 70 eV 150 eV
200 eV 250 eV 300 eV
![Page 20: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/20.jpg)
Circular Electric Field
40 eV 70 eV 150 eV
200 eV 250 eV 300 eV
![Page 21: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/21.jpg)
Conclusions
• Results confirm validity of our numerical implementation
• Orientation of polarization has significant impact on final result
![Page 22: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/22.jpg)
Future Work
• Use longer wavelengths (infrared light)
• Include nuclear motion
• Address more complex molecular systems
![Page 23: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/23.jpg)
Acknowledgements
• Mentors– Dr. Xiaoxu Guan – Dr. Klaus Bartschat
• Project support through NSF
![Page 24: Ionization of the Hydrogen Molecular Ion by Ultrashort Intense Elliptically Polarized Laser Radiation Ryan DuToit Xiaoxu Guan (Mentor) Klaus Bartschat.](https://reader035.fdocuments.in/reader035/viewer/2022062305/56649cc25503460f94989711/html5/thumbnails/24.jpg)
Questions?