View source for Alexander K. Zaichenko

{{Infobox scientist
| name = Alexander K. Zaichenko
| fields = Theoretical physics
| workplaces = Institute for Nuclear Research, National Academy of Sciences of Ukraine
| known_for = Tunnelling times and the generalized Hartman effect
}}

'''Alexander K. Zaichenko''' is a physicist at the Institute for Nuclear Research of the National Academy of Sciences of Ukraine, in Kiev, known for his work on the quantum theory of tunnelling times and superluminal tunnelling. He is listed in ''[[The Worldwide List of Dissident Scientists]]''.

==Work==
Zaichenko has collaborated with Vladislav S. Olkhovsky and Erasmo Recami on the analysis of the time spent by a particle tunnelling through a potential barrier. Their work proposed new definitions for sub-barrier tunnelling and reflection times within conventional quantum mechanics, including a treatment of the so-called "Hartman effect" — the observation that the tunnelling duration becomes independent of the width of an opaque barrier, a result whose group velocities can be superluminal. These ideas were developed in the paper "More About Tunnelling Times, the Dwell Time, and the 'Hartman Effect'" (1995) and in related reviews.

With Sergei P. Maydanyuk and Olkhovsky he also developed a "method of multiple internal reflections" for describing the tunnelling evolution of non-relativistic particles and photons. His interests extend to interference phenomena in the spectra of alpha particles emitted in nuclear reactions such as p+<sup>11</sup>B→3α.

The superluminal interpretation of tunnelling group velocities associated with this line of research lies outside the mainstream consensus on signal propagation, which is why de Climont catalogued it under the heading "Superluminal."

==External links==
* [https://arxiv.org/abs/quant-ph/9508010 "More About Tunnelling Times, the Dwell Time, and the 'Hartman Effect'" (arXiv)]
* [https://arxiv.org/abs/nucl-th/0407108 "The method of multiple internal reflections in a description of tunneling evolution..." (arXiv)]

[[Category:Scientist|Zaichenko Alexander]]
[[Category:Worldwide List of Dissident Scientists]]