Controllable light group velocity in a degenerate two-level medium under the assistance of an external magnetic field



  • Hoang Minh Dong Ho Chi Minh City University of Industry and Trade
  • Thai Doan Thanh Ho Chi Minh City University of Industry and Trade
  • Nguyen Thi Thu Hien Ho Chi Minh City University of Industry and Trade
  • Trang Huynh Dang Khoa Ho Chi Minh City University of Industry and Trade
  • Le Van Doai Vinh University
  • Nguyen Manh Thang (Corresponding Author) Academy of Military Science and Technology



Electromagnetically induced transparency; Electromagnetically induced absorption; Degenerate two-level atomic; Group index; Group velocity; Subluminal and superluminal light propagation.


In this work, we proposed a simple model for control of subluminal and superluminal light propagation via an external magnetic field in a lambda configuration degenerate two-level atomic medium. We show that the absorption-dispersion properties and group index under the influence of the strength of coupling laser and external magnetic fields are controlled. By changing the direction and magnitude of the magnetic field, the medium switches from transparency with normal dispersion to enhanced absorption with anomalous dispersion at the line center, corresponding with the transfer from slow light to fast light. This work may provide for the application realization of magneto-optic switches and storage devices in quantum information processing.


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How to Cite

Hoang Minh, D., Thai Doan Thanh, Nguyen Thi Thu Hien, Trang Huynh Dang Khoa, Le Van Doai, and Nguyen Manh Thang. “Controllable Light Group Velocity in a Degenerate Two-Level Medium under the Assistance of an External Magnetic Field”. Journal of Military Science and Technology, vol. 93, no. 93, Feb. 2024, pp. 106-13, doi:10.54939/1859-1043.j.mst.93.2024.106-113.



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