Negative Refractive Index in an Inhomogeneously Broadened Four-Level Inverted-Y Atomic Medium
Authors: Nguyen Thanh Cong, Nguyen Huy Bang , Nguyen Van Phu, Vu Ngoc Sau and Le Van Doai
IEEE Photonics Journal
: 10.1109 / JPHOT.2021.3119985 : 1-7
Publishing year: 12/2021
In this paper, we present the study on negative refractive
index in an inhomogeneously broadened four-level inverted-
Y atomic medium based on electromagnetically induced transparency
(EIT). The expressions of the relative permittivity and
the relative permeability are derived under Doppler broadening.
For this four-level system, we have found two frequency bands of
negative refractive index in an optical region corresponding to two
EIT windows. The influences of coupling and signal laser fields
as well as temperature on frequency bands of negative refractive
index are investigated. Our research can be convenient for experimental
implementation with real atomic media under different
temperatures.
Index Terms—Negative refractive index, electromagnetically induced transparency, doppler broadening.
