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Title: Ultrashort pulse control of space-dependent excitations in a three-level system

Abstract

Coherent control of regions with spatial excitation of populations and coherence between two lower states in three-level {lambda}-type quantum systems mediated by the self-induced transparency (SIT) phenomenon is theoretically investigated with one- and two-color ultrashort pulses and with pulse sequences beyond the slowly varying envelope (SVEA) and rotating wave (RWA) approximations. The effects of different parameters characterizing the pulses and the medium on the location as well as the width of such excited regions have been studied numerically by means of the finite-difference time-domain (FDTD) method. It has been determined that with a scheme of two-pulse excitation one can effectively control the position at which the region is written and its width. In particular, the position of the excited region can be controlled by the area of the pulses. We find that the maximum value of the population transferred to the lower excited state depends on the detuning of the pulses with respect to the one-photon resonances, and that both position and width of the region also depend on the temporal duration of the pulses. We show how after the excited region is written, its position can be shifted by additional pulses. On the basis of numerical results, scaling lawsmore » are formulated for the reported phenomena. With such control, the width of the region excited inside the medium can be reduced to the order of the wavelength of the light.« less

Authors:
 [1];  [2]; ;  [3];  [4];  [5]; ;  [4]
  1. Departament de Fisica i Enginyeria Nuclear, Universitat Politecnica de Catalunya, Colom 11, 08222 Terrassa, (Spain)
  2. (Belarus)
  3. Departament de Fisica i Enginyeria Nuclear, Universitat Politecnica de Catalunya, Colom 11, 08222 Terrassa (Spain)
  4. Departament de Fisica, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain)
  5. (Spain)
Publication Date:
OSTI Identifier:
20982177
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.023801; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; APPROXIMATIONS; COLOR; CONTROL; EXCITATION; EXCITED STATES; FINITE DIFFERENCE METHOD; OPACITY; PHOTONS; PULSES; RESONANCE; SCALING LAWS; SPACE DEPENDENCE; VELOCITY; VISIBLE RADIATION; WAVELENGTHS

Citation Formats

Loiko, Yu., Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, Nezaleznasty Ave. 70, 220072 Minsk,, Serrat, C., Vilaseca, R., Ahufinger, V., ICREA-Institucio Catalana de Recerca i Estudis Avancats, Barcelona, Mompart, J., and Corbalan, R. Ultrashort pulse control of space-dependent excitations in a three-level system. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.023801.
Loiko, Yu., Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, Nezaleznasty Ave. 70, 220072 Minsk,, Serrat, C., Vilaseca, R., Ahufinger, V., ICREA-Institucio Catalana de Recerca i Estudis Avancats, Barcelona, Mompart, J., & Corbalan, R. Ultrashort pulse control of space-dependent excitations in a three-level system. United States. doi:10.1103/PHYSREVA.75.023801.
Loiko, Yu., Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, Nezaleznasty Ave. 70, 220072 Minsk,, Serrat, C., Vilaseca, R., Ahufinger, V., ICREA-Institucio Catalana de Recerca i Estudis Avancats, Barcelona, Mompart, J., and Corbalan, R. Thu . "Ultrashort pulse control of space-dependent excitations in a three-level system". United States. doi:10.1103/PHYSREVA.75.023801.
@article{osti_20982177,
title = {Ultrashort pulse control of space-dependent excitations in a three-level system},
author = {Loiko, Yu. and Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, Nezaleznasty Ave. 70, 220072 Minsk, and Serrat, C. and Vilaseca, R. and Ahufinger, V. and ICREA-Institucio Catalana de Recerca i Estudis Avancats, Barcelona and Mompart, J. and Corbalan, R.},
abstractNote = {Coherent control of regions with spatial excitation of populations and coherence between two lower states in three-level {lambda}-type quantum systems mediated by the self-induced transparency (SIT) phenomenon is theoretically investigated with one- and two-color ultrashort pulses and with pulse sequences beyond the slowly varying envelope (SVEA) and rotating wave (RWA) approximations. The effects of different parameters characterizing the pulses and the medium on the location as well as the width of such excited regions have been studied numerically by means of the finite-difference time-domain (FDTD) method. It has been determined that with a scheme of two-pulse excitation one can effectively control the position at which the region is written and its width. In particular, the position of the excited region can be controlled by the area of the pulses. We find that the maximum value of the population transferred to the lower excited state depends on the detuning of the pulses with respect to the one-photon resonances, and that both position and width of the region also depend on the temporal duration of the pulses. We show how after the excited region is written, its position can be shifted by additional pulses. On the basis of numerical results, scaling laws are formulated for the reported phenomena. With such control, the width of the region excited inside the medium can be reduced to the order of the wavelength of the light.},
doi = {10.1103/PHYSREVA.75.023801},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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