Interference control of photodissociation branching ratios. Two-color frequency tuning of intense laser fields
✍ Scribed by Zhidang Chen; Moshe Shapiro; Paul Brumer
- Book ID
- 103032448
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 525 KB
- Volume
- 228
- Category
- Article
- ISSN
- 0009-2614
No coin nor oath required. For personal study only.
✦ Synopsis
Control over product probabilities and channel specific line shapes in molecular photodissociation is shown to result from quantum interference effects which can be manipulated by varying the frequencies of two intense laser fields. The laser fields, whose relative phase need not be well defined, have frequencies centered around two transitions: one between the continuum and an initially populated state and the second between the continuum and an initially unpopulated molecular bound state. Computations on Na2 photodissociation show that control over product yields is extensive, with the branching ratio changing by a factor of ten as the frequencies are tuned over a convenient range.
Laser control of atomic and molecular processes is a rapidly developing field. Most recent innovations rely on using several lasers with well defined relative phase to excite a system [ l-8 1. The quantum interference between the laser induced multiple excitation routes depends upon both the laser intensities and their relative phases. Hence, by varying these laboratory parameters one varies the interference, leading to experimentally controllable molecular dynamics. Extensive control over processes such as branching in molecular photodissociation has been demonstrated computationally and several experiments have supported the essential principle [ 61.
In this Letter, we demonstrate that high laser fields introduce nonlinear phenomena which allow novel and effective control scenarios. Specifically, we show that one can control channel specific line shapes and photodissociation branching ratios using two-color