자료유형  

 학위논문

Control Number  

0017162982

International Standard Book Number  

9798384345596

Dewey Decimal Classification Number  

530.41

Main Entry-Personal Name  

Werby, Nicholas.

Publication, Distribution, etc. (Imprint  

[S.l.] : Stanford University., 2024

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

131 p.

General Note  

Source: Dissertations Abstracts International, Volume: 86-03, Section: B.

General Note  

Advisor: Bucksbaum, Philip.

Dissertation Note  

Thesis (Ph.D.)--Stanford University, 2024.

Summary, Etc.  

요약The ultrafast dynamics of strong-field tunnel ionization are recorded within intricate interference patterns in photoelectron momentum distributions. We categorize these dynamics with quantum electron trajectories which outline the possible paths an electron may take on its way to the detector. The pair-wise interference of these trajectories give rise to the holograms observable in strong-field spectra. These trajectories are determined by only three parameters: their ionization phases in the ionizing field, their initial transverse momenta, and the shape of the laser field they subsequently propagate within. The laser field tends to be a measurable quantity and the initial transverse momentum can often be inferred from the electron's position on the detector; however, experimentally measuring ionization phases is much more difficult. Existing techniques to measure these ionization phases are commonly stymied in the presence of multiple contributing trajectories, each with their own ionization phase, which reduces their viability when probing electron holograms. To more effectively study electron holograms in strong-field spectra, I developed two powerful techniques which help unlock the ionization phase of electron trajectories as an experimental observable. I methodically apply these techniques to strong-field ionized photoelectron momentum distributions of atomic argon to assess their effectiveness through comparisons with quantitative calculations of strong-field trajectory interference.The first technique, the time-correlation filter, employs a differential Fourier analysis to reveal, isolate, or selectively remove individual holograms based on the ionization time separation of the pair of trajectories forming them. This has broad implications for experimentally measuring trajectories forming holographic structure. As one example, by removing unwanted intercycle interference structures I reveal a new hologram modulating the prominent spider-leg hologram. Furthermore, by isolating this new hologram in a defined window of time separations, I trace its origin to a specific class of electron trajectory which weakly interacts with the residual parent ion interfering with trajectories ionized half a laser cycle earlier. In order to test the validity of the technique, I make multiple comparisons of time-correlation filtered experimental data to calculations of specific pairs of interfering trajectories and show excellent agreement. Because the time-correlation filter is an analysis technique and does not require any experimental modification, it can be applied to all energy- and angularly-resolved datasets to measure pairwise interference in a broad range of strong-field ionization spectra. Additionally, the results of the time-correlation filter are independent of theory, and so can be used to directly measure time separations from an experiment, without relying on comparisons to supporting calculations from trajectory-based models of strong-field dynamics.The second technique, three-color ionization phase extraction, involves adding a small, phase-controlled, second and third harmonic perturbation to the ionizing laser field to directly measure the ionization phases of multiple trajectories arriving at each momentum bin on the detector. To examine the benefits of a three-laser-color system, I present the predecessor technique of two-color phase-of-the-phase analysis on a high-resolution experimental dataset. I reveal how it effectively measures the ionization phase of trajectories arriving at regions of the detector where they are the heavily dominant or only trajectory, yet fails to extract even a single relevant phase in regions with more than one trajectory of comparable amplitude. With three laser colors, I outline how to extract the ionization phases of the two highest amplitude electron trajectories and compare to calculation to show quantitative agreement to within 5 degrees of phase, which corresponds to 37 attoseconds for an 800nm laser. The success of this technique is a persuasive argument in favor of employing three-color laser probes in future studies of strong-field dynamics.

Subject Added Entry-Topical Term  

Anisotropy.

Subject Added Entry-Topical Term  

Energy.

Subject Added Entry-Topical Term  

Lasers.

Subject Added Entry-Topical Term  

Electric fields.

Subject Added Entry-Topical Term  

Orbits.

Subject Added Entry-Topical Term  

Electromagnetics.

Subject Added Entry-Topical Term  

Optics.

Added Entry-Corporate Name  

Stanford University.

Host Item Entry  

Dissertations Abstracts International. 86-03B.

Electronic Location and Access  

로그인을 한후 보실 수 있는 자료입니다.

Control Number  

joongbu:657114