The design and operation of a proof-of-principle rectangular He-Ne ring laser resonator with a cavity perimeter of 77.0 m and an area of ~367 m<sup>2</sup> are described. With unevacuated beam lines this device gave an Earth-induced Sagnac frequency of 1513 Hz, with a relative Allan deviation over 1000 s down to 3 parts per million. The Earth’s rotation provided a bias that eliminated the lock-in susceptibility. The use of increased pressure in the plasma tube facilitated single-mode operation by increasing the homogeneous pressure-broadened linewidth.
© 2002 Optical Society of America
Robert W. Dunn, Dmitry E. Shabalin, Robert J. Thirkettle, Graeme J. MacDonald, Geoffrey E. Stedman, and K. Ulrich Schreiber, "Design and Initial Operation of a 367-m2 Rectangular Ring Laser," Appl. Opt. 41, 1685-1688 (2002)