Abstract

The harmonic spectra generated by atoms in the presence of an ionized neighborhood are investigated. Numerical calculations in a one-dimensional model show an increase of the maximum harmonic energy radiated that leads to photon frequencies well beyond the single-atom cutoff Ip + 3.17Up. We identify these harmonics with those generated when the atom’s detached electron is captured by a neighboring ion. By means of classical considerations, we give simple laws for the new harmonic cutoff in the tunneling and the multiphoton ionization regimes.

© 1996 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. See, e.g., Atoms in Intense Laser Fields, M. Gavrila, ed., Advances in Atomic, Molecular, and Optical Physics (Academic, New York, 1992), Suppl. 1.
  2. A. L’Huillier, K. J. Schafer, and K. C. Kulander, Phys. Rev. Lett. 66, 2200 (1991).
    [CrossRef]
  3. L. Plaja and L. Roso, in SuperIntense Laser–Atom Physics, B. Piraux, A. L’Huillier, and K. Rzazewski, eds. (Plenum, New York, 1993), pp. 53–61.
    [CrossRef]
  4. J. L. Krause, K. J. Schafer, and K. C. Kulander, Phys. Rev. A 45, 4998 (1992).
    [CrossRef] [PubMed]
  5. P. B. Corkum, N. H. Burnett, and F. Brunel, Phys. Rev. Lett. 62, 1259 (1989).
    [CrossRef] [PubMed]
  6. M. Lewenstein, Ph. Balcou, M. Yu. Ivanov, A. L’Huillier, and P. B. Corkum, Phys. Rev. A 49, 2117 (1994).
    [CrossRef] [PubMed]
  7. K. J. Schafer, B. Yang, L. F. DiMauro, and K. C. Kulander, Phys. Rev. Lett. 71, 1599 (1993).
    [CrossRef]
  8. Q. Su and J. H. Eberly, Phys. Rev. A 44, 5997 (1991).
    [CrossRef] [PubMed]
  9. P. Moreno, L. Plaja, and L. Roso, Europhys. Lett. 28, 629 (1994).
    [CrossRef]

1994 (2)

M. Lewenstein, Ph. Balcou, M. Yu. Ivanov, A. L’Huillier, and P. B. Corkum, Phys. Rev. A 49, 2117 (1994).
[CrossRef] [PubMed]

P. Moreno, L. Plaja, and L. Roso, Europhys. Lett. 28, 629 (1994).
[CrossRef]

1993 (1)

K. J. Schafer, B. Yang, L. F. DiMauro, and K. C. Kulander, Phys. Rev. Lett. 71, 1599 (1993).
[CrossRef]

1992 (1)

J. L. Krause, K. J. Schafer, and K. C. Kulander, Phys. Rev. A 45, 4998 (1992).
[CrossRef] [PubMed]

1991 (2)

Q. Su and J. H. Eberly, Phys. Rev. A 44, 5997 (1991).
[CrossRef] [PubMed]

A. L’Huillier, K. J. Schafer, and K. C. Kulander, Phys. Rev. Lett. 66, 2200 (1991).
[CrossRef]

1989 (1)

P. B. Corkum, N. H. Burnett, and F. Brunel, Phys. Rev. Lett. 62, 1259 (1989).
[CrossRef] [PubMed]

Balcou, Ph.

M. Lewenstein, Ph. Balcou, M. Yu. Ivanov, A. L’Huillier, and P. B. Corkum, Phys. Rev. A 49, 2117 (1994).
[CrossRef] [PubMed]

Brunel, F.

P. B. Corkum, N. H. Burnett, and F. Brunel, Phys. Rev. Lett. 62, 1259 (1989).
[CrossRef] [PubMed]

Burnett, N. H.

P. B. Corkum, N. H. Burnett, and F. Brunel, Phys. Rev. Lett. 62, 1259 (1989).
[CrossRef] [PubMed]

Corkum, P. B.

M. Lewenstein, Ph. Balcou, M. Yu. Ivanov, A. L’Huillier, and P. B. Corkum, Phys. Rev. A 49, 2117 (1994).
[CrossRef] [PubMed]

P. B. Corkum, N. H. Burnett, and F. Brunel, Phys. Rev. Lett. 62, 1259 (1989).
[CrossRef] [PubMed]

DiMauro, L. F.

K. J. Schafer, B. Yang, L. F. DiMauro, and K. C. Kulander, Phys. Rev. Lett. 71, 1599 (1993).
[CrossRef]

Eberly, J. H.

Q. Su and J. H. Eberly, Phys. Rev. A 44, 5997 (1991).
[CrossRef] [PubMed]

Ivanov, M. Yu.

M. Lewenstein, Ph. Balcou, M. Yu. Ivanov, A. L’Huillier, and P. B. Corkum, Phys. Rev. A 49, 2117 (1994).
[CrossRef] [PubMed]

Krause, J. L.

J. L. Krause, K. J. Schafer, and K. C. Kulander, Phys. Rev. A 45, 4998 (1992).
[CrossRef] [PubMed]

Kulander, K. C.

K. J. Schafer, B. Yang, L. F. DiMauro, and K. C. Kulander, Phys. Rev. Lett. 71, 1599 (1993).
[CrossRef]

J. L. Krause, K. J. Schafer, and K. C. Kulander, Phys. Rev. A 45, 4998 (1992).
[CrossRef] [PubMed]

A. L’Huillier, K. J. Schafer, and K. C. Kulander, Phys. Rev. Lett. 66, 2200 (1991).
[CrossRef]

L’Huillier, A.

M. Lewenstein, Ph. Balcou, M. Yu. Ivanov, A. L’Huillier, and P. B. Corkum, Phys. Rev. A 49, 2117 (1994).
[CrossRef] [PubMed]

A. L’Huillier, K. J. Schafer, and K. C. Kulander, Phys. Rev. Lett. 66, 2200 (1991).
[CrossRef]

Lewenstein, M.

M. Lewenstein, Ph. Balcou, M. Yu. Ivanov, A. L’Huillier, and P. B. Corkum, Phys. Rev. A 49, 2117 (1994).
[CrossRef] [PubMed]

Moreno, P.

P. Moreno, L. Plaja, and L. Roso, Europhys. Lett. 28, 629 (1994).
[CrossRef]

Plaja, L.

P. Moreno, L. Plaja, and L. Roso, Europhys. Lett. 28, 629 (1994).
[CrossRef]

L. Plaja and L. Roso, in SuperIntense Laser–Atom Physics, B. Piraux, A. L’Huillier, and K. Rzazewski, eds. (Plenum, New York, 1993), pp. 53–61.
[CrossRef]

Roso, L.

P. Moreno, L. Plaja, and L. Roso, Europhys. Lett. 28, 629 (1994).
[CrossRef]

L. Plaja and L. Roso, in SuperIntense Laser–Atom Physics, B. Piraux, A. L’Huillier, and K. Rzazewski, eds. (Plenum, New York, 1993), pp. 53–61.
[CrossRef]

Schafer, K. J.

K. J. Schafer, B. Yang, L. F. DiMauro, and K. C. Kulander, Phys. Rev. Lett. 71, 1599 (1993).
[CrossRef]

J. L. Krause, K. J. Schafer, and K. C. Kulander, Phys. Rev. A 45, 4998 (1992).
[CrossRef] [PubMed]

A. L’Huillier, K. J. Schafer, and K. C. Kulander, Phys. Rev. Lett. 66, 2200 (1991).
[CrossRef]

Su, Q.

Q. Su and J. H. Eberly, Phys. Rev. A 44, 5997 (1991).
[CrossRef] [PubMed]

Yang, B.

K. J. Schafer, B. Yang, L. F. DiMauro, and K. C. Kulander, Phys. Rev. Lett. 71, 1599 (1993).
[CrossRef]

Europhys. Lett. (1)

P. Moreno, L. Plaja, and L. Roso, Europhys. Lett. 28, 629 (1994).
[CrossRef]

Phys. Rev. A (3)

J. L. Krause, K. J. Schafer, and K. C. Kulander, Phys. Rev. A 45, 4998 (1992).
[CrossRef] [PubMed]

M. Lewenstein, Ph. Balcou, M. Yu. Ivanov, A. L’Huillier, and P. B. Corkum, Phys. Rev. A 49, 2117 (1994).
[CrossRef] [PubMed]

Q. Su and J. H. Eberly, Phys. Rev. A 44, 5997 (1991).
[CrossRef] [PubMed]

Phys. Rev. Lett. (3)

K. J. Schafer, B. Yang, L. F. DiMauro, and K. C. Kulander, Phys. Rev. Lett. 71, 1599 (1993).
[CrossRef]

P. B. Corkum, N. H. Burnett, and F. Brunel, Phys. Rev. Lett. 62, 1259 (1989).
[CrossRef] [PubMed]

A. L’Huillier, K. J. Schafer, and K. C. Kulander, Phys. Rev. Lett. 66, 2200 (1991).
[CrossRef]

Other (2)

L. Plaja and L. Roso, in SuperIntense Laser–Atom Physics, B. Piraux, A. L’Huillier, and K. Rzazewski, eds. (Plenum, New York, 1993), pp. 53–61.
[CrossRef]

See, e.g., Atoms in Intense Laser Fields, M. Gavrila, ed., Advances in Atomic, Molecular, and Optical Physics (Academic, New York, 1992), Suppl. 1.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (5)

Fig. 1
Fig. 1

Maximum kinetic energies acquired by a classical electron at every point of space, considering all the possible trajectories coming from different initial conditions of the field (0 < ζ ≤ 2π). Initial velocities are 0, 0.32, and 0.47 a.u., corresponding to tunneling (circles), minimum photon number (12 photons; triangles), and 1-photon excess (13 photons; ×’s) multiphoton ionization regimes. The field intensity is 0.05 a.u. The laser frequency ωL is taken to be 0.06 a.u., and the ionization energy is Ip = 0.67 a.u. The inset shows an amplification of the z ≈ 0 region.

Fig. 2
Fig. 2

Harmonic spectra from the ion–atom system for different distances between them. Laser conditions are chosen to be well inside the tunneling limit. This figure corresponds to E0 = 0.08 a.u. and ωL = 0.06 a.u., with three cycles of linear turn-on followed by five cycles of constant field. The energy of the fundamental state of the atom and of the ion is Ip = 0.67 a.u.

Fig. 3
Fig. 3

Harmonic spectra from the ion–atom system for different distances between them. Laser conditions are chosen to be in a mixed tunneling–multiphoton regime. This figure corresponds to E0 = 0.05 a.u. and ωL = 0.06 a.u., with five cycles of linear turn-on followed by ten cycles of constant field.

Fig. 4
Fig. 4

Comparison between (a) the single-atom harmonic spectra and (b) the integrated spectra over 100 atom–ion systems. Ions are assumed to be randomly distributed over a region of 2πα0 around the parent atom. The tunneling conditions depicted are the same as for Fig. 2 (E0 = 0.08 a.u. and ωL = 0.06 a.u., with three cycles of linear turn-on followed by five cycles of constant field).

Fig. 5
Fig. 5

Comparison between (a) the single-atom harmonic spectra and (b) the integrated spectra over 100 atom–ion systems. Ions are assumed to be randomly distributed over a region of 2πα0 around the parent atom. The figure depicts the same mixed tunneling–multiphoton regime as in Fig. 3 (E = 0.05 a.u. and ωL = 0.06 a.u., with five cycles of linear turn-on followed by ten cycles of constant field).

Equations (5)

Equations on this page are rendered with MathJax. Learn more.

i t φ ( z , t ) = [ 1 2 2 z 2 + V ( z ) ] φ ( z , t ) 1 c A 0 ( t ) cos ( ω L t ) z φ ( z , t ) ,
V ( z ) = 1 [ ( z z e ) 2 + 1 ] 1 / 2 1 [ ( z z r ) 2 + 1 ] 1 / 2 ,
d 2 z d t 2 = E 0 sin ( ω L t + ζ ) , d z d t = v 0 + E 0 ω L [ cos ( ζ ) + cos ( ω L t + ζ ) ] , z = v 0 t + E 0 ω L 2 [ ω L t cos ( ζ ) + sin ( ω L t + ζ ) sin ( ζ ) ] ,
T max = 1 2 ( v 0 + 4 U p ) 2 ,
z T max = m π ( v 0 / ω L + α 0 )

Metrics