Erasing the traces of classical mechanics in ionization of H2 by quantum interferences

O A FOJÓN; C R STIA; R D RIVAROLA

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AMER PHYSICAL SOC

Lugar: New York; Año: 2011 vol. 84 p. 32715 - 32715

1050-2947

The single ionization of hydrogen molecules by fast electron impact is studied theoretically for transitions from the ground (gerade) state to final ground (gerade) and first-excited (ungerade) states of H2+. It is shown that  under definite conditions and for particular orientations of the molecule, the main physical features of the ionization reaction, which are the binary and recoil peaks usually associated with classical mechanisms, are completely erased by quantum interference effects that resemble the ones predicted previously for photoionization reactions. However, these new effects cannot be derived from photoionization results, as the electromagnetic field cannot transfer momentum. In addition, it is found that the emission spectra of transitions leading to the final gerade and ungerade states of the H2+ residual target are analogous in certain cases to the patterns of two sources emitting waves in phase or antiphase, respectively. Finally, we show how an average of the emission from randomly oriented molecules produces a binary peak at the classical expected position, in agreement with experiments.