Sagnac interferometry and temporal cloaking via Raman gain

The phenomenon of temporal cloaking (TC) via Raman gain is explored using Sagnac interferometer (SI) and atomic medium coupling. As a function of the pump field detuning, the temporal gap extends from 6 ms to 20 ms, with the presence of Raman gain in the system. Whereas, with variations in the control field phase angle, a temporal gap of 10 ms is achieved within the system. Similarly, the time delay/advance reaches to ±2 ms and ±5 ms. Additionally, positive and negative improved group refractive index is observed accompanied by negative and positive relativistic group velocities. The presented results may find applications in secure communication, image coding/design, and secure rotation sensing technologies.