Electrons in electric and magnetic fields
Photoionization of negatively charged ions leads to a system of a neutral atom and the detached electron (photodetachment). Interestingly, the presence of external fields during this process allows to control the detachment rate (the total current) and the differential cross section [12].
We develop theoretical methods to calculate the cross section and current distribution. The semiclassical analysis of the resulting currents shows how a complicated underlying classical trajectory skeleton is transformed to a quantum mechanical interference pattern [2,14]. The pattern yield precise information about the energy of the detached electron and can be used to extract i.e. electron affinities with very high precision.
In an electric field, the interference fringes have been experimentally recorded with the help of the photodetachment microscope by Prof. Dr. Christophe Blondel, Laboratoire Aimé Cotton, France.
The presence of an magnetic field causes a particular strong modulation of the photodetachment cross section [5-8]. Our theory is in excellent agreement with experimental data [5].
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| (a) Four path interference for the focussing region in parallel electric and magnetic fields [2,14] |
References
| [30] | Fluctuations in the spectra of open few-body systems | ||
| J. Eiglsperger, T. Kramer, J. Madroñero | |||
| New Journal of Physics, in press (2011) | article | Open Access | |
| [17] | New mathematical tools for quantum technology | ||
| C. Bracher, M. Kleber, and T. Kramer | |||
| Mathematics of Quantum Computation and Technology, edited by G. Chen, L. Kauffman, S. Lomonaco, Chapman & Hill/CRC (2007) | book | arxiv | |
| [14] | Electron dynamics in parallel electric and magnetic fields | ||
| C. Bracher, T. Kramer, and J. Delos | |||
| Phys. Rev. A, 73, 062114-1-21, (2006) | article | arxiv | |
| [12] | The photoelectric effect in external fields | ||
| C. Bracher, J. Delos, V. Kanellopoulos, M. Kleber, and T. Kramer | |||
| Physics Letters A, 317, 62-66, (2005) | article | arxiv | |
| [8] | Propagation in crossed magnetic and electric fields: The quantum source approach | ||
| T. Kramer and C. Bracher | |||
| Symmetries in Science XI, Edited by B. Gruber, G. Marmo, and N. Yoshinaga, Kluwer, Dordrecht, (2004) | book | arxiv | |
| [7] | Matter waves from localized quantum sources | ||
| T. Kramer | |||
| Squeezed States and Uncertainty Relations, Edited by H. Moya-Cessa et al., pp. 210-217, Rinton Press, Princeton, NJ (2003) | book | arxiv | |
| [6] | Electron propagation in crossed magnetic and electric fields | ||
| T. Kramer, C. Bracher, and M. Kleber | |||
| J. Opt. B: Quantum Semiclass. Opt., 6, 21-27, (2004) | article | arxiv | |
| [5] | Observed photodetachment in parallel electric and magnetic fields | ||
| J.N. Yukich, T. Kramer, and C. Bracher | |||
| Phys. Rev. A, 68, 033412-1-8, (2003) | article | arxiv | |
| [4] | Ballistic matter waves with angular momentum: Exact solutions and applications | ||
| C. Bracher, T. Kramer, and M. Kleber | |||
| Phys. Rev. A, 67, 043601, (2003) | article | arxiv | |
| [3] | Matter waves from quantum sources in a force field | ||
| T. Kramer, C. Bracher, and M. Kleber | |||
| J. Phys. A: Math. Gen., 35, 8361, (2002) | article | arxiv | |
| [2] | Four-path interference and uncertainty principle in photodetachment microscopy | ||
| T. Kramer, C. Bracher, and M. Kleber | |||
| Europhys. Lett., 56, 471, (2001) | article | arxiv | |