Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Optics and Spectroscopy

Laser-induced radiative recombination of antihydrogen in a magnetic field through a quasi-stationary state

Vladislav Viktorovich Serov, Vladimir Leonardovich Derbov, Sergue Il'ich Vinitsky

Published Apr 1, 2007• 7 citations
Publisher

Abstract

To increase the efficiency of laser-induced recombination of antihydrogen from cold antihydrogen—positron plasma in a trap, it is proposed to use a new resonance mechanism with the participation of positron quasi-stationary states, arising under the joint action of an antiproton Coulomb field and a strong magnetic field of the trap. The recombination rate is expressed through the atomic laser ionization cross section whose frequency dependence is nonmonotonic due to the presence of quasi-stationary states against the background of the continuum. The estimates with the use of the ionization cross sections calculated earlier demonstrate the possibility of improving the efficiency of the laser-induced recombination at an optimally selected laser frequency.

DOI
10.1134/s0030400x07040133

Related papers

Laser-stimulated radiative recombination of antihydrogen in a magnetic field in the presence of Doppler broadening

Vladislav Viktorovich Serov, Vladimir Leonardovich Derbov, V. I. Lobanov +3 more

To enhance the laser-stimulated recombination of antihydrogen from cold antiproton-positron plasma in a trap we propose to use a new resonance mechanism involving the quasi-stationary states of the positron that arise from the joint action of the Coulomb field of the antiproton and the strong magnetic field of the trap. The recombination rate is expressed via the cross-section of laser ionization of the atom that has strongly non-monotonic frequency dependence due to the presence of quasi-stationary states merged into the continuum background. The estimates using previously calculated ionization cross-section show the possibility to enhance the laser-stimulated recombination by means of the optimal laser frequency choice.

•Jun 13, 2007•0 citations

Laser-induced antiproton-positron recombination in traps

Maria V. Ryabinina, Leonid A. Melnikov, Vladimir Leonardovich Derbov +1 more

Summary form only given. In the present report we propose a combination of pulsed electric field and laser pulse field at wavelength near 800 nm to stimulate the formation of antihydrogen atoms in lower states (n = 3) in positron-antiproton plasma under the conditions of Penning and Paul traps at low temperatures. The laser intensity estimated is about dozens of W/cm/sup 2/. In crossed constant magnetic field and circularly polarized alternating electric fields a new kind of stationary rotating wave packet states were shown to arise in hydrogen-like systems under special conditions. These packets, knows as Trojan states, remain strongly localized and thus differ significantly from common Rydberg states. Using numerical modeling of wave packet dynamics we analyse the stability of these states with respect to field perturbations and estimate the possibility to use them as intermediate states for antihydrogen production. We discuss the polarization dependencies of the laser-induced recombination rate for the case of the anisotropic velocity distribution.

Quantum Electronics and Laser Science Conference•Jun 25, 2003•1 citation

Collisions between anti-particles in presence of laser field

Chittaranjan Sinha, S. Ghosh Deb

Three body recombination (TBR) process for the formation of antihydrogen () inside a trapped plasma of antiprotons () and positrons (e+), supposed to be the most efficient mechanism for the production of cold and trapped antihydrogen is studied quantum mechanically. Present study also involves a background laser field anticipating further enhancement of the formation cross sections. Significantly large cross sections are obtained in the presence of the field at lower incident energies as compared to the field free ones. Cross sections are enhanced for higher excited states of ().

Journal of Physics Conference Series•Sep 1, 2009•0 citations

Formation of antihydrogen in an antiproton-positron Debye plasma in the presence of an external laser field

Sougata Mukhopadhyay, Chittaranjan Sinha

We study quantum mechanically the influence of an external laser field on the antihydrogen ($\overline{\mathrm{H}}$) formation cross sections in ground and excited states (2$s$,2$p$) via the three-body recombination process inside a dense plasma of antiprotons and positrons, supposed to be the most efficient mechanism for cold and trapped antihydrogen. The plasma screening is considered in the framework of a Debye- H\"uckel potential. The laser polarization is chosen to be parallel to the incident momentum of the passive positron. The modifications due to the presence of the laser field are found to be quite significant both quantitatively and qualitatively for all the states. In the presence of a laser, the $\overline{\mathrm{H}}$ formation cross sections are found to be suppressed significantly with respect to the field-free situation particularly in the ground state, while the excited state cross sections are in general enhanced at very low incident energies but are again suppressed at higher energies except for some special cases. The sensitivity of the formation cross sections with respect to the Debye length are also studied both in the laser-assisted and in the field-free situations. At very low incident energies, the ground state multiphoton formation is found to enhance with the increase in Debye screening, while the reverse is true for the excited states. These findings should have important implications for future $\overline{\mathrm{H}}$ studies.

Physical Review A•Sep 11, 2013•10 citations

Spontaneous recombination of antihydrogen in a magnetic field: a new approach

Vladislav Viktorovich Serov, Vladimir Leonardovich Derbov

We propose a new mechanism that can contribute to the spontaneous recombination of antihydrogen atoms in traps containing cold positron-antiproton plasma in the presence of a constant magnetic field. The latter plays a principal role restricting the motion of the positron in the transverse plane and, finally, prolonging the time during which the positron can lose its energy due to spontaneous radiation. Classical and quantum mechanical estimates are presented under the conditions close to those experimentally realized in the existing traps.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jul 13, 2004•2 citations

Large numbers of cold positronium atoms created in laser-selected Rydberg states using resonant charge exchange

Robert McConnell, G. Gabrielse, W. Steven Kolthammer +10 more

Abstract Lasers are used to control the production of highly excited positronium atoms (Ps*). The laser light excites Cs atoms to Rydberg states that have a large cross section for resonant charge-exchange collisions with cold trapped positrons. For each trial with 30 million trapped positrons, more than 700 000 of the created Ps* have trajectories near the axis of the apparatus, and are detected using Stark ionization. This number of Ps* is 500 times higher than realized in an earlier proof-of-principle demonstration (2004 Phys. Lett. B 597 257). A second charge exchange of these near-axis Ps* with trapped antiprotons could be used to produce cold antihydrogen, and this antihydrogen production is expected to be increased by a similar factor.

Journal of Physics B Atomic Molecular and Optical Physics•Feb 23, 2016•14 citations
To increase the efficiency of laser-induced recombination of antihydrogen from cold antihydrogen—positron plasma in a trap, it is proposed to use a new resonance mechanism with the participation of positron quasi-stationary states, arising under the joint action of an antiproton Coulomb field and a strong magnetic field of the trap. The recombination rate is expressed through the atomic laser ionization cross section whose frequency dependence is nonmonotonic due to the presence of quasi-stationary states against the background of the continuum. The estimates with the use of the ionization cross sections calculated earlier demonstrate the possibility of improving the efficiency of the laser-induced recombination at an optimally selected laser frequency.
To enhance the laser-stimulated recombination of antihydrogen from cold antiproton-positron plasma in a trap we propose to use a new resonance mechanism involving the quasi-stationary states of the positron that arise from the joint action of the Coulomb field of the antiproton and the strong magnetic field of the trap. The recombination rate is expressed via the cross-section of laser ionization of the atom that has strongly non-monotonic frequency dependence due to the presence of quasi-stationary states merged into the continuum background. The estimates using previously calculated ionization cross-section show the possibility to enhance the laser-stimulated recombination by means of the optimal laser frequency choice.
Summary form only given. In the present report we propose a combination of pulsed electric field and laser pulse field at wavelength near 800 nm to stimulate the formation of antihydrogen atoms in lower states (n = 3) in positron-antiproton plasma under the conditions of Penning and Paul traps at low temperatures. The laser intensity estimated is about dozens of W/cm/sup 2/. In crossed constant magnetic field and circularly polarized alternating electric fields a new kind of stationary rotating wave packet states were shown to arise in hydrogen-like systems under special conditions. These packets, knows as Trojan states, remain strongly localized and thus differ significantly from common Rydberg states. Using numerical modeling of wave packet dynamics we analyse the stability of these states with respect to field perturbations and estimate the possibility to use them as intermediate states for antihydrogen production. We discuss the polarization dependencies of the laser-induced recombination rate for the case of the anisotropic velocity distribution.
Three body recombination (TBR) process for the formation of antihydrogen () inside a trapped plasma of antiprotons () and positrons (e+), supposed to be the most efficient mechanism for the production of cold and trapped antihydrogen is studied quantum mechanically. Present study also involves a background laser field anticipating further enhancement of the formation cross sections. Significantly large cross sections are obtained in the presence of the field at lower incident energies as compared to the field free ones. Cross sections are enhanced for higher excited states of ().
We study quantum mechanically the influence of an external laser field on the antihydrogen (H‾\overline{\mathrm{H}}H) formation cross sections in ground and excited states (2sss,2ppp) via the three-body recombination process inside a dense plasma of antiprotons and positrons, supposed to be the most efficient mechanism for cold and trapped antihydrogen. The plasma screening is considered in the framework of a Debye- H\"uckel potential. The laser polarization is chosen to be parallel to the incident momentum of the passive positron. The modifications due to the presence of the laser field are found to be quite significant both quantitatively and qualitatively for all the states. In the presence of a laser, the H‾\overline{\mathrm{H}}H formation cross sections are found to be suppressed significantly with respect to the field-free situation particularly in the ground state, while the excited state cross sections are in general enhanced at very low incident energies but are again suppressed at higher energies except for some special cases. The sensitivity of the formation cross sections with respect to the Debye length are also studied both in the laser-assisted and in the field-free situations. At very low incident energies, the ground state multiphoton formation is found to enhance with the increase in Debye screening, while the reverse is true for the excited states. These findings should have important implications for future H‾\overline{\mathrm{H}}H studies.
We propose a new mechanism that can contribute to the spontaneous recombination of antihydrogen atoms in traps containing cold positron-antiproton plasma in the presence of a constant magnetic field. The latter plays a principal role restricting the motion of the positron in the transverse plane and, finally, prolonging the time during which the positron can lose its energy due to spontaneous radiation. Classical and quantum mechanical estimates are presented under the conditions close to those experimentally realized in the existing traps.
Abstract Lasers are used to control the production of highly excited positronium atoms (Ps*). The laser light excites Cs atoms to Rydberg states that have a large cross section for resonant charge-exchange collisions with cold trapped positrons. For each trial with 30 million trapped positrons, more than 700 000 of the created Ps* have trajectories near the axis of the apparatus, and are detected using Stark ionization. This number of Ps* is 500 times higher than realized in an earlier proof-of-principle demonstration (2004 Phys. Lett. B 597 257). A second charge exchange of these near-axis Ps* with trapped antiprotons could be used to produce cold antihydrogen, and this antihydrogen production is expected to be increased by a similar factor.