We theoretically propose and experimentally perform a novel dispersion tuning scheme to realize a tunable Fano resonance in a coupled-resonator-induced transparency (CRIT) structure coupled Mach-Zehnder interferometer. We reveal that the profile of the Fano resonance in the resonator coupled Mach-Zehnder interferometers (RCMZI) is determined not only by the phase shift difference between the two arms of the RCMZI but also by the dispersion (group delay) of the CRIT structure. Furthermore, it is theoretically predicted and experimentally demonstrated that the slope and the asymmetry parameter (q) describing the Fano resonance spectral line shape of the RCMZI experience a sign reversal when the dispersion of the CRIT structure is tuned from abnormal dispersion (fast light) to normal dispersion (slow light). These theoretical and experimental results indicate that the reversible Fano resonance which holds significant implications for some attractive device applications such as highly sensitive biochemical sensors, ultrafast optical switches and routers can be realized by the dispersion tuning scheme in the RCMZI.
In this article, we present a simple method to realize a sensor of ultrahigh sensitivity and compact size by employing a feedback double ring resonator. We demonstrate that this method has not only a higher sensitivity than an optimal add-drop resonator (ADR), but also a relatively high performance when the Q factor drops. Furthermore, we show that this sensing system can overcome the limitation of Q factor on system sensitivity by 2 orders of magnitude in comparison to the corresponding ADR. Thus, the proposal in this paper provides a promising and feasible scheme to realize a highly effective sensor that is weakly dependent on the Q factor of the system.
We propose the modulation period and amplitude of the typical square wave phase bias modulation (SWPBM) applicable to a resonator-based interferometric fiber-optic gyroscope (R-IFOG) and theoretically study the performance of the R-IFOG under SWPBM. Under SWPBM of the proposed modulation period and amplitude, the R-IFOG possesses a performance distinct from that under the hypothetical time-independent phase bias. Also, the sensitivity of the R-IFOG with SWPBM to a slow rotation rate is boosted in comparison to that without phase bias, and the rotation direction can be indicated. Furthermore, the ultrahigh sensitivity can be attained by an R-IFOG of an extremely short fiber length when the R-IFOG with SWPBM consists of a high finesse resonator. Therefore, the SWPBM of the proposed modulation period and amplitude enables highly sensitive and compact integrated closed-loop R-IFOGs. in 2009. He is currently pursuing his PhD degree at Harbin Institute of Technology, Harbin, China. His current research interests include coupled resonator-based sensors, optical interconnects, and photon scattering on atoms in one-dimensional waveguides.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.