Description: The essential elements that characterize the performance of a laser gyro are (a) a bidirectional ring laser, (b) a lightweight, efficient instrument (c) a high sensitivity to rotation and (d) a linear response without dead band. To address (c), substantial enhancement has been predicted through large intracavity dispersion; we have demonstrated this property in a mode-locked laser with intracavity Fabry-Perot etalon, yielding a decrease in response due to the fact that the Kramers-Kronig dispersion of the Fabry-Perot is positive. The objective of Phase I is to experimentally demonstrate an enhancement using a Gires-Tournois interferometer for dispersion control, in combination with demonstrating the absence of dead band (d) in a solid state laser. A key element is the realization that it is possible to engineer a mode-locked laser where the pulse envelope velocity is controlled by other parameters than the dispersion. This property will be exploited in Phase I by inserting in a ring mode-locked Ti:sapphire laser a Gires-Tournois and a Rubidium cell, to demonstrate simultaneously the enhancement of the gyro sensitivity, the use of a solid state gain medium in a gyro, and the absence of dead band. We will also prepare for Phase II, in which these results will be implemented in a mode-locked fiber laser gyro, to demonstrate the light and efficient instrument required for space applications.

Benefits: A light weight expandable gyro has application in commercial and space navigation in earth orbit as well as in deep space. Because the fiber laser can be made of very large perimeter, it has applications in monitoring the motion of tectonic plates. Further development can transform this device into a linear accelerometer.

Non-NASA applications in existing markets are the uses in aerospace and naval navigation, especially if these gyros are included in Inertial Measurement Units (IMU). Emerging market segments are the LOON project of Google and the high-altitude drones planned by Facebook (both to provide network access for remote regions), micro- and nano-satellites (SpaceX), or commercial space flight (Virgin).