Single short pulse generated by hydrogen atom exposed to the combined field of two laser pulses with similar frequency

Abstract

Abstract: The high order harmonic generations of three-dimensional hydrogen atom which exposed to the combination of two laser pulses have been studied. When the combined field has a proper frequency ratio(3:5), and the relative intensity of the additional laser field reaches a specific value(0.35), the single short pulse can be obtained directly. A new method to obtain the single short pulse is proposed, the main points of the method are: the frequency ratio of the two lasers should be adjacent odd, and the relative intensity of the additional laser to the basic laser should fall on a particular value. In future research, the atoms with a higher binding energy can be chosen, the width of HHG’s plateau will be enlarged, so the width of pulse will be reduced.

Key words: laser physics, single short pulse; bichromatic laser field, high order harmonic generations of three-dimensional hydrogen atom, quantum pathway

CLC Number:

TN241

YANG Yiting, QIAO Haoxue. Single short pulse generated by hydrogen atom exposed to the combined field of two laser pulses with similar frequency[J]. J4, 2013, 30(4): 405-410.

References

[1] Corkum P B. Plasma perspective on strong field multiphoton ionization. 1993 Phys.Rev.Lett. 71 1994
[2] Sansone G, Beendetti E, Calegari F, Vozzi C, Avaldi L, Flammini R, Poletto L, Villoresi P, Altucci C, Velotta R, Stagira S, Silvestri S D, Nisoli M. Isolated Single-Cycle Attosecond Pulses. 2006 Science 314 443
[3] Lan P F, Lu P X, Cao W, Wang X L. Efficient generation of an isolated single-cycle attosecond pulse. 2007 Phys.Rev.A. 76 043808
[4] Zeng Z, Cheng Y, Song X et al. Generation of an Extreme Ultraviolet Supercontinuum in a Two-Color Laser Field. 2007 Phys.Rev.Lett. 98 203901
[5] Zhai Z, Liu X S. Extension of the high-order harmonics and an isolated sub-100 as pulse generation in a two-colour laser field. 2008 Journal of Physics B 41 125602
[6]Hentschel M, Kienberger R, Spielmann C, Reider G A, Milosevic N, Brabec T, Corkum P, Heinzmann U, Drescher M, Krausz F. Attosecond metrology[J].2001 Nature, 414 509-513.
[7] Ye X L, Zhou X X, Zhao S F, Li P C. The single attosecond pulse generated by atom exposed to two-color combined laser field (in Chinese). 2009 Acta Phys.Sin. (Chinese Ver) 58(3) 1580
[8] Pan H L, Li P C, Zhou XX. Single attosecond pulse generated by atom exposed to two laser pulses with the same color and half cycle pulses (in Chinese). 2011 Acta Phys.Sin. (Chinese Ver) 60(4) 043203
[9] Pan H L, Wang G L, Zhou X X. Single attosecond pulse generated by helium atom exposed to the combined field of two laser pulses with the same color and midinfrared intense laser pulse (in Chinese). 2011 Acta Phys.Sin. (Chinese Ver) 60(4) 043203
[10] Cai J, Qiao H X. Pathway of bichromatic high-order harmonic generationg. 2007 Phys.Rev.A. 75 035801
[11] Cai J, Wang L M, Qiao H X. Phase dependent quantum interference between different pathways in bichromatic harmonic generation. 2009 Chinese Physics B. 18 1458
[12] Qiao H X, Cai Q Y, Rao J G, et al. Spectral fitting method for the solution of time-dependent Schr?dinger equations: Applications to atoms in intense laser fields. 2002 Phys.Rev.A. 65(6) 063403
[13] Hermann M R, Fleck J A. Split-operator spectral method for solving the time-dependent Schr?dinger equation in spherical coordinates. 1988 Phys.Rev.A. 38(12) 6000
[14] Burnett K, Reed V C, Cooper J, Knight P L. Calculation of the background emitted during high-harmonic generation. 1992 Phys.Rev.A. 45 3347
[15] Jarque E C, Plaja L. Harmonic generation with ionizing two-level atoms. 1998 Journal of Physics B: Atomic, Molecular and Optical Physics 31 1687
[16] Faria C, Dorr M, Sandner W. Importance of excited bound states in harmonic generation. 1998 Phys.Rev.A.58 2990
[17] Gaarde M B, L’Huillier A, Lewenstein M. Theory of high-order sum and difference frequency mixing in a strong bichromatic laser field. 1996 Phys.Rev.A. 54 4236