Strong laser field control

In this reaction the strong laser field controls not only the breaking but also the forming of bonds because the toluene product cannot be formed without a rearrangement. The experiment is by Levis et al. (2001). Hurley and Castleman (2001) provide a commentary. A review of the experimental capabilities is Brixner and Gerber (2003). 

In this contribution recent results [13] on the control of the quantum mechanical phase of an atomic state in strong laser fields studied using the Autler-Townes (AT) effect [14] in the photoionization of the K (4p) state are discussed. We demonstrate quantum control beyond (i) population control and (ii) spectral interference, (i) We show, that for suitable combinations of the laser intensity of the first pulse and the time delay the second resonant intense laser pulse leaves the excited state population unchanged. However, the knowledge of the... 

Another property of atoms which is sensitive to the conditions in the outer reaches of the atomic field is of course orbital collapse, which can be controlled as described in section 5.23. This has led Golovinskiy et al. [480] to consider whether a strong laser field could be used to precipitate orbital collapse, and to propose an experiment in which dynamic collapse at the Rabi frequency could be detected by X-ray spectroscopy of the irradiated sample. 

In the present chapter, the rapidly growing subject of atoms in strong laser fields has been briefly described, the main emphasis being on the novel effects which have been observed. Several aspects of the problem have not been discussed for example, above 1020 Wcm-2, relativistic effects will become important, although these have not yet been observed. Similarly, we have omitted any discussion of coherent control in two-colour excitation and femtosecond chemistry. 

As before, the essence of coherent control by a strong laser field consists in transferring the molecular system at hand from the initial state F)into the desired final state Ff). This should be achieved by means of a tailored electric field, A(t), that enters into the Schrodinger equation... 

In Section 6.3.2, we presented experimental data from strong-field excitation and ionization of K atoms with shaped femtosecond laser pulses. Here we give a description of the apparatus and strategy used in the experiments presented in this contribution. Figure 6.12 gives an overview over the complete experimental two-color setup. For the experiments on strong-field control of K atoms (cf Sections 6.3.2.2, 6.3.2.3, and 6.5) only the one-color beamline was used. An... 

Models describing the transport of electrons in molecular junctions have been shown to be quite powerful. Here the emphasis was put on time-dependent effects which can, for example, be triggered by external laser fields. If these fields are strong, a non-perturbative treatment of the laser-matter interaction is of large importance and is included in the presented TL QME. Also the connection of transport through molecular wires or coherent laser control scenarios may play an important role in the future. 

Consider the problem of wave packet control in a weak laser field. Here wave packet control refers to the creation of a wave packet at a given target position on a specific electronic potential energy surface at a selected time tf. For this purpose, a variational treatment is introduced. In the weak field limit, the wave packet can be calculated by first-order perturbation theory without the need to solve explicitly the time-dependent Schrodinger equation. In strong fields, where the perturbative treatment breaks down, the time-dependent Schrodinger equation must be explicitly taken into account, as will be discussed in later sections. 

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