The advent of electromagnetically induced transparency (EIT) offered a new coherent material with exotic and controllable optical properties. Extension from single to multiple EIT is of current interest because it gains advantages in multi-channel optical communication, waveguides for optical signal processing and multi-channel quantum information processing. | Communications in Physics, Vol. 29, No. 1 (2019), pp. 1-33 DOI: REVIEW PAPER CONTROLLABLE OPTICAL PROPERTIES OF MULTIPLE ELECTROMAGNETICALLY INDUCED TRANSPARENCY IN GASEOUS ATOMIC MEDIA BANG NGUYEN HUY † , DOAI LE VAN AND KHOA DINH XUAN Vinh University, 182 Le Duan street, Vinh City, Vietnam † E-mail: bangnh@ Received 9 October 2018 Accepted for publication 29 November 2018 Published 31 January 2019 Abstract. The advent of electromagnetically induced transparency (EIT) offered a new coherent material with exotic and controllable optical properties. Extension from single to multiple EIT is of current interest because it gains advantages in multi-channel optical communication, waveguides for optical signal processing and multi-channel quantum information processing. In this work, we review recent research works concerning multiple EIT and some related applications such as controlling group velocity of light, giant Kerr nonlinearity, optical bistability. The special attention of the review is also on analytical interpretations of the results to give physics insight and suitable applications. From an experimental point of view, the latest development for measuring multiple EIT spectrum and its dispersion in hot medium is presented and compared to the theoretical analytical representations. Keywords: effects of atomic coherence. Classification numbers: ; ; . c 2019 Vietnam Academy of Science and Technology 2 CONTROLLABLE OPTICAL PROPERTIES OF MULTIPLE ELECTROMAGNETICALLY . I. INTRODUCTION The EIT is a quantum interference effect which makes a resonance medium transparent and steeper dispersion for a probe light field under induction of a strong coupling light field. The effect was proposed theoretically in 1989 [1] and experimentally verified in 1991 [2]. Since then, the EIT has attracted much studies in atomic/molecular systems [3–14] and quantum well/dot systems [15–19] due to its unusual
