Symmetry Violation of Time Reversal in High Order Nonlinear Stimulated Radiation and Absorption Processes of Light (original) (raw)
Related papers
2003
It is proved that when the retarded effect (or multiple moment effect) of radiation fields is taken into account, the light's high order stimulated radiation and stimulated absorption probabilities are not the same so that time reversal symmetry would be violated, though the total Hamiltonian of electromagnetic interaction is still unchanged under time reversal. The reason to cause time reversal symmetry violation is that certain filial or partial transitive processes of bounding state atoms are forbidden or can't be achieved actually due to the law of energy conservation, the asymmetric actions of effective transition operators before and after time reversal, as well as the special states of atoms themselves. These restrictions would cause the symmetry violation of time reversal of other filial or partial transition processes which can be actualized really. The symmetry violation is also relative to the initial state's asymmetries of bounding atoms before and after time reversal. For the electromagnetic interaction between non-bounding state's atoms and radiation field, there is no this kind of symmetry violation of time reversal. In this way, the current formula of light's stimulated radiation and absorption parameters with time reversal symmetry should be revised. The influence of time reversal symmetry violation on the foundational theory of laser is also discussed and the phenomena of non-population inversion and non-radiation transition can also be explained well. In this way, a more reliable foundation can be established for the theories of laser and nonlinear optics in which non-equilibrium processes are involved.
Science in China Series G: Physics, Mechanics and Astronomy, 2008
It has been proved that when the retarded effect (or multiple moment effect) of radiation fields is taken into account, the high order stimulated radiation and stimulated absorption probabilities of light are not the same so that time reversal symmetry would be violated, though the Hamiltonian of electromagnetic interaction is still unchanged under time reversal. The reason to cause time reversal symmetry violation is that certain filial or partial transition processes of bound atoms are forbidden or cannot be achieved due to the law of energy conservation and the special states of atoms themselves. These restrictions would cause the symmetry violation of time reversal of other filial or partial transition processes which can be actualized really. The symmetry violation is also relative to the asymmetry of initial states of bound atoms before and after time reversal. For the electromagnetic interaction between non-bound atoms and radiation field, there is no such kind of symmetry violation of time reversal. In this way, the current formula on the parameters of stimulated radiation and absorption of light with time reversal symmetry should be revised. A more reliable foundation can be established for the theories of laser and nonlinear optics in which non-equilibrium processes are involved.
2008
Based on Document (1), by considering the retarded interaction of radiation fields, the third order transition probabilities of stimulated radiations and absorptions of light are calculated. The revised formulas of nonlinear polarizations are provided. The results show that that the general processes of non-linear optics violate time reversal symmetry. The phenomena of non-linear optics violating time reversal symmetry just as sum frequency, double frequency, different frequencies, double stable states, self-focusing and self-defocusing, echo phenomena, as well as optical self-transparence and self absorptions and so on are analyzed.
Time reversal noninvariance in quantum mechanics and in nonlinear optics
The experimental proofs of strong time invariance violation in optics are discussed. Time noninvariance is the only real physical base for explanation the origin of the most phenomena in nonlinear optics. The experimental study of forward and reversed transitions in oriented in uniform electric field molecules is proposed.
Time reversal in matter-wave optics
The European Physical Journal D, 2011
The evolution of atomic wave packets experiencing so-called comoving potential pulses is examined theoretically, in the framework of the stationary-phase approximation. The negative refraction induced by this potential is a characteristic property of negative-index media, the atomic counterpart of negative-index materials of light optics. A novel process, specific of negative-index for matter waves, is evidenced, namely a narrowing of the wave packet transiently counterbalancing the natural spreading. This is the manifestation of a general property of negative-index media, i.e. a time reversal effect. It is shown that, for a statistical ensemble of wave packets leading to a moderate dispersion of the times of flight, this time reversal phenomenon should be observable.
Nuclear Physics A, 1968
An explicit derivation of a general property of symmetry of the non-local optical potential is given by using the projection operators. Such a property, which in a particular case reduces to the symmetry in the position coordinates, insures the relation of reciprocity and follows from the reversibility of the original multi-channel system. * The sense of the term reciprocity used in this paper is defined in sect. 2 and is the same as in ref. ~).
Chemical Physics, 2007
Pulse shaping of femtosecond lasers causes frequency and intensity changes in the electromagnetic field; these changes can be symmetric or asymmetric with respect to time. Within the first few femtosecond, the nonlinear optical response is purely electronic. The nuclear response follows soon after that and continues for hundreds of femtoseconds. Differences in the nonlinear optical response caused by time inversion of laser pulses are explored here on a number of different systems. The change in behavior is first probed in a solution of IR144 for different laser intensities which shows a distinctive asymmetry upon time inversion in the fluorescence signal above the linear response regime. Two-photon induced fluorescence of a rhodamine B solution at high intensities is found to have a symmetric phase dependence which becomes asymmetric because of self phase modulation and self focusing at higher laser intensities. Surprisingly, the fragmentation and ionization of isolated para-nitrotoluene molecules was found not to depend on time inversion of the shaped laser pulses. However, from pulse shaping experiments we can glean the relative timing of the fragmentation processes. Results from this study show that the response of a system to time inversion of shaped femtosecond pluses provides an internal clock for ultrafast physicochemical processes occurring during laser-matter interactions.
Time Asymmetric Quantum Mechanics and Shock Waves: Exploring the Irreversibility in Nonlinear Optics
Annalen der Physik
The description of irreversible phenomena is a still debated topic in quantum mechanics. Still nowadays, there is no clear procedure to distinguish the coupling with external baths from the intrinsic irreversibility in isolated systems. In 1928 Gamow introduced states with exponentially decaying observables not belonging to the conventional Hilbert space. These states are named Gamow vectors, and they belong to rigged Hilbert spaces. This review summarizes the contemporary approach using Gamow vectors and rigged Hilbert space formalism as foundations of a generalized "time asymmetric" quantum mechanics. We study the irreversible propagation of specific wave packets and show that the topic is surprisingly related to the problem of irreversibility of shock waves in classical nonlinear evolution. We specifically consider the applications in the field of nonlinear optics. We show that it is possible to emulate irreversible quantum mechanical process by the nonlinear evolution of a laser beam and we provide experimental tests by the generation of dispersive shock waves in highly nonlocal regimes. We demonstrate experimentally the quantization of decay rates predicted by the time-asymmetric quantum mechanics. This work furnishes support to the idea of intrinsically irreversible wave propagation, and to novel tests of the foundations of quantum mechanics.