Colloquium: Aligning molecules with strong laser pulses

Colloquium: Aligning molecules with strong laser pulses

2003-04-17 | Stapelfeldt, Henrik; Seideman, Tamar
This review discusses the theoretical and experimental status of intense laser alignment, a technique at the intersection of intense laser physics and chemical dynamics with potential applications in high harmonic generation, nanoscale processing, stereodynamics, and chemical reaction control. The paper compares intense laser alignment with other alignment techniques and explains the physics behind the method, including the roles of laser frequency, pulse duration, and system temperature. It also describes methods for observing alignment in the laboratory and extends the concept to three-dimensional orientational control, which hinders rotation about all three axes of polyatomic molecules. The paper concludes with a discussion of potential applications of intense laser alignment. The paper is organized into sections covering theory, experimental observation of alignment, applications of alignment, and a conclusion. In the theory section, the physical origin of intense laser alignment is discussed within a quantum-mechanical framework. The paper focuses on the qualitative concepts and omits technical details. It begins with the physics of conventional (1D) laser alignment and extends the discussion to 3D alignment. Atomic units are used throughout. In the one-dimensional alignment section, the paper discusses near-resonant vs nonresonant alignment and adiabatic vs dynamical alignment. It explains how polarized laser pulses of sufficient intensity and duration can readily populate broad rotational wave packets at either near-resonant or nonresonant frequencies. It also discusses the conditions under which such wave packets necessarily align. In the three-dimensional alignment section, the paper discusses how an elliptically polarized intense field can eliminate the rotation in all three Euler angles of polyatomic molecules. It also discusses the role of the laser frequency, pulse duration, and rotational temperature in the alignment process. The paper also discusses experimental observations of alignment, including one-dimensional adiabatic alignment, one-dimensional nonadiabatic alignment, and three-dimensional adiabatic alignment. It describes methods for observing alignment in the laboratory, including photodissociation and ion imaging. The paper concludes with a discussion of potential applications of intense laser alignment, including control of photoabsorption/photodissociation, probe of nonradiative transitions, and other applications. It also discusses the advantages and disadvantages of intense laser alignment compared to other alignment techniques.This review discusses the theoretical and experimental status of intense laser alignment, a technique at the intersection of intense laser physics and chemical dynamics with potential applications in high harmonic generation, nanoscale processing, stereodynamics, and chemical reaction control. The paper compares intense laser alignment with other alignment techniques and explains the physics behind the method, including the roles of laser frequency, pulse duration, and system temperature. It also describes methods for observing alignment in the laboratory and extends the concept to three-dimensional orientational control, which hinders rotation about all three axes of polyatomic molecules. The paper concludes with a discussion of potential applications of intense laser alignment. The paper is organized into sections covering theory, experimental observation of alignment, applications of alignment, and a conclusion. In the theory section, the physical origin of intense laser alignment is discussed within a quantum-mechanical framework. The paper focuses on the qualitative concepts and omits technical details. It begins with the physics of conventional (1D) laser alignment and extends the discussion to 3D alignment. Atomic units are used throughout. In the one-dimensional alignment section, the paper discusses near-resonant vs nonresonant alignment and adiabatic vs dynamical alignment. It explains how polarized laser pulses of sufficient intensity and duration can readily populate broad rotational wave packets at either near-resonant or nonresonant frequencies. It also discusses the conditions under which such wave packets necessarily align. In the three-dimensional alignment section, the paper discusses how an elliptically polarized intense field can eliminate the rotation in all three Euler angles of polyatomic molecules. It also discusses the role of the laser frequency, pulse duration, and rotational temperature in the alignment process. The paper also discusses experimental observations of alignment, including one-dimensional adiabatic alignment, one-dimensional nonadiabatic alignment, and three-dimensional adiabatic alignment. It describes methods for observing alignment in the laboratory, including photodissociation and ion imaging. The paper concludes with a discussion of potential applications of intense laser alignment, including control of photoabsorption/photodissociation, probe of nonradiative transitions, and other applications. It also discusses the advantages and disadvantages of intense laser alignment compared to other alignment techniques.
Reach us at info@study.space