Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Europhysics Letters (EPL)

Sagnac interferometry and temporal cloaking via Raman gain

Sana Ullah, Arif Ullah, Muhammad Imtiaz Khan, Muhammad Javed, Mehdi Akermi, Muneerah Amer Alomar

Published Jul 1, 2025• 0 citations
Publisher

Abstract

Abstract 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.

DOI
10.1209/0295-5075/adee42

Related papers

Sagnac interferometry and temporal cloaking via conductivity–dependent cross–Kerr nonlinearity

Sana Ullah, Arif Ullah, Muneerah Amer Alomar +1 more

We theoretically investigate temporal cloaking (TC) in a Sagnac interferometer using conductivity-dependent cross-Kerr nonlinearity (CKN). By altering the phase and strength of conductivity, we observe changes in the effectiveness of TC, variations in relativistic group velocities (RGV), and shifts in the group index. The group index attains values up to [Formula: see text] depending on the phase angles [Formula: see text]. Similarly, the window of temporal gaps increases as a function of [Formula: see text] and the phase of conductivity, with higher conductivity strengths. The maximum temporal gap is [Formula: see text][Formula: see text]s. These results will contribute to advancement in secure quantum communication and precision rotation sensing technologies.

Journal of Nonlinear Optical Physics & Materials•Aug 15, 2025•0 citations

The impact of cross-Kerr nonlinearity on rotary photon drag and temporal cloaking in Sagnac interferometry

Sana Ullah, Arif Ullah, Rashid Ahmad +1 more

Abstract We theoretically explore the impact of cross-Kerr nonlinearity (CKN) on rotary photon drag (RPD) and temporal cloaking in a Sagnac interferometer. With the activation of CKN, significant improvements in RPD and temporal cloaking are observed. Drag angles of ± 1 × 10 − 3 and ± 5 × 10 − 3 radians are attained, similarly, temporal gaps of 10 μ s, 12 μ s and 13 μ s are observed. In addition to the observed electromagnetically induced transparency window, the group refractive index is drastically enhanced, time delay/advance are tuned from pico-radians to micro-radians, and reduced relativistic group velocities are achieved by activating CKN within the system. Additionally, the transmission pulses intensities are observed to be reduced with the dragging phenomenon. The findings may have potential applications in controlled image coding, rotation sensing and secure communication technologies.

Journal of Optics•Jun 3, 2024•7 citations

Sagnac interferometry and the impact of conductivity-dependent Raman gain on rotary photon drag

Sana Ullah, Arif Ullah, Muhammad Javed +1 more

Abstract We theoretically demonstrate the impact of conductivity-dependent Raman gain (RG) on rotary photon drag (RPD) in a Sagnac interferometer (SI). The presence of conductivity-dependent Raman gain results in enhanced RPD angles, ranging from θ d = ± 0.56 radians to θ d = ± 0.7 radians. The susceptibility, group index, relativistic group velocities, and RPD exhibit significant fluctuations with changes in the conductivity phase. Specifically, we observe gain-singlets when the control field is deactivated, while gain doublets are achieved when the control field is activated. Moreover, within the gain regions, we observe normal dispersion, whereas anomalous dispersion is observed around the gain regions. These findings have potential applications in controlled image coding/design, four-wave mixing, photo detectors, light modulation, and phase-matching in Brillouin scattering.

Physica Scripta•Jan 3, 2024•3 citations

Sagnac interferometry and self-Kerr nonlinearity dependent photon drag

Sana Ullah, Arif Ullah, Bakht Amin Bacha +1 more

Abstract We present a theoretical investigation of the photon drag by incorporating self-Kerr nonlinearity (SKN) in a Sagnac interferometer featuring a four-level atomic system. By introducing SKN in the system, we demonstrate significant improvements in the photon drag angles, ranging from ±10 micro-radians to ±1 centi-radians. Additionally, the presence of SKN leads to electromagnetically induced transparency (EIT), reduced group velocities, and a positive group index enhancement within the system. Conversely, in the absence of SKN, a negative group index is observed, accompanied by larger group velocities and minimal photon drag angles. The results obtained may have potential applications in various fields, such as slow-light detection, controlled image coding/design, efficient light modulators, and phase-matching in Brillouin scattering.

Europhysics Letters (EPL)•Jul 25, 2023•5 citations

Controllable Anomalous Dispersion and Group Index Nulling via Bi-Frequency Raman Gain in Rb Vapor for application to Ultraprecision Rotation Sensing

G. S. Pati, Renu Tripathi, M. Messall +2 more

We have recently proposed [9], the use of fast-light media to obtain ultrahigh precision rotation sensing capabilities. The scheme relies on producing a critically anomalous dispersion, in a suitable dispersive medium, which is introduced in the arms of a Sagnac interferometer. We present here an experimental investigation of the anomalous dispersion properties of bi-frequency Raman gain in rubidium vapor, with the goal of using this medium for producing the critically anomalous dispersion condition. A heterodyne phase measurement technique is used to measure accurately the index variation associated with the dispersion. The slope of the negative linear dispersion (or group index) is experimentally varied by more than two orders of magnitude while changing the frequency separation between pump fields, responsible for producing gain. Using this result, we have identified the experimental parameters for achieving a null value of the group index, corresponding to the critically anomalous dispersion condition necessary for enhanced rotational sensitivity.

arXiv:quant-ph/0512260•Dec 30, 2005•1 citation

Controllable anomalous dispersion and group index nulling via bi-frequency Raman gain for ultraprecision rotation sensing

G. S. Pati, Renu Tripathi, M. Messall +3 more

Using a bi-frequency pumped Raman amplifier in a Rb vapor cell, we demonstrate experimentally the condition for achieving a null group index, necessary for fast-light enhanced rotation sensing in a passive cavity Sagnac gyroscope.

Conference on Lasers and Electro-Optics•Jan 1, 2006•1 citation
Abstract 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.
We theoretically investigate temporal cloaking (TC) in a Sagnac interferometer using conductivity-dependent cross-Kerr nonlinearity (CKN). By altering the phase and strength of conductivity, we observe changes in the effectiveness of TC, variations in relativistic group velocities (RGV), and shifts in the group index. The group index attains values up to [Formula: see text] depending on the phase angles [Formula: see text]. Similarly, the window of temporal gaps increases as a function of [Formula: see text] and the phase of conductivity, with higher conductivity strengths. The maximum temporal gap is [Formula: see text][Formula: see text]s. These results will contribute to advancement in secure quantum communication and precision rotation sensing technologies.
Abstract We theoretically explore the impact of cross-Kerr nonlinearity (CKN) on rotary photon drag (RPD) and temporal cloaking in a Sagnac interferometer. With the activation of CKN, significant improvements in RPD and temporal cloaking are observed. Drag angles of ± 1 × 10 − 3 and ± 5 × 10 − 3 radians are attained, similarly, temporal gaps of 10 μ s, 12 μ s and 13 μ s are observed. In addition to the observed electromagnetically induced transparency window, the group refractive index is drastically enhanced, time delay/advance are tuned from pico-radians to micro-radians, and reduced relativistic group velocities are achieved by activating CKN within the system. Additionally, the transmission pulses intensities are observed to be reduced with the dragging phenomenon. The findings may have potential applications in controlled image coding, rotation sensing and secure communication technologies.
Abstract We theoretically demonstrate the impact of conductivity-dependent Raman gain (RG) on rotary photon drag (RPD) in a Sagnac interferometer (SI). The presence of conductivity-dependent Raman gain results in enhanced RPD angles, ranging from θ d = ± 0.56 radians to θ d = ± 0.7 radians. The susceptibility, group index, relativistic group velocities, and RPD exhibit significant fluctuations with changes in the conductivity phase. Specifically, we observe gain-singlets when the control field is deactivated, while gain doublets are achieved when the control field is activated. Moreover, within the gain regions, we observe normal dispersion, whereas anomalous dispersion is observed around the gain regions. These findings have potential applications in controlled image coding/design, four-wave mixing, photo detectors, light modulation, and phase-matching in Brillouin scattering.
Abstract We present a theoretical investigation of the photon drag by incorporating self-Kerr nonlinearity (SKN) in a Sagnac interferometer featuring a four-level atomic system. By introducing SKN in the system, we demonstrate significant improvements in the photon drag angles, ranging from ±10 micro-radians to ±1 centi-radians. Additionally, the presence of SKN leads to electromagnetically induced transparency (EIT), reduced group velocities, and a positive group index enhancement within the system. Conversely, in the absence of SKN, a negative group index is observed, accompanied by larger group velocities and minimal photon drag angles. The results obtained may have potential applications in various fields, such as slow-light detection, controlled image coding/design, efficient light modulators, and phase-matching in Brillouin scattering.
We have recently proposed [9], the use of fast-light media to obtain ultrahigh precision rotation sensing capabilities. The scheme relies on producing a critically anomalous dispersion, in a suitable dispersive medium, which is introduced in the arms of a Sagnac interferometer. We present here an experimental investigation of the anomalous dispersion properties of bi-frequency Raman gain in rubidium vapor, with the goal of using this medium for producing the critically anomalous dispersion condition. A heterodyne phase measurement technique is used to measure accurately the index variation associated with the dispersion. The slope of the negative linear dispersion (or group index) is experimentally varied by more than two orders of magnitude while changing the frequency separation between pump fields, responsible for producing gain. Using this result, we have identified the experimental parameters for achieving a null value of the group index, corresponding to the critically anomalous dispersion condition necessary for enhanced rotational sensitivity.