Fast Light Enhanced Active and Passive Gyroscopes, Accelerometers and Fiber- Optic Sensors

The fast-light effect in a cavity, produced by anomalous dispersion, has emerged as an important mechanism for enhancing the sensitivity of many devices. There are two modes of operation of such a cavity. In the active mode, the system is a superluminal ring laser (SRL) that experiences an anomalous dispersion caused by the gain medium. In the passive mode, the system is a white light cavity (WLC) that experiences an anomalous dispersion caused by an intra-cavity medium or via coupling to another cavity or another mode in the same cavity. We will investigation the development several closely related technologies based on the fast light effect: gyroscopes, accelerometers and general purpose fiber-optic sensors. For each technology, we will primarily pursue the active approach. The gyroscope will be based on using a pair of spatially overlapping SRLs realized via Raman gains, with Raman depletion used for anomalous dispersion. The accelerometer will be realized by using a similar system, but with two lasers that are spatially shifted with respect to each other. The fiber-optic sensor will be based on using a pair of Brillouin gain based SRLs, where the anomalous dispersion is produced via coupling to a cavity. In addition, for each device, we will investigate theoretically some passive techniques in order to determine relative advantages and tradeoffs between the two approaches. Specifically, for the gyroscope and the accelerometer, we will investigate the use of couple cavity based WLCs; for the fiber-optic sensor, we will investigate the use of a WLC realized by dual-peaked Brillouin gain. The particular mode of operation to be pursued for developing a practical version of each of these devices under Phase II will be established in accordance with the findings of the Phase I effort, and potential feedback and guidance received from the NASA program manager. Northwestern University, with Prof. Shahriar as the PI, will be a subcontractor.