R. W. Terhune

Ruby as a Maser Material

The reasons for the initial choice of ruby as a maser material are outlined and some measurements of the parameters in the spin Hamiltonian and of spin relaxation times are reported. The relative merits of single‐ and double‐pump modes of operation of a four‐level maser are discussed and measurements of the oscillator power for the two cases are included.

Rapid-Scan Spectroscopy with a Fabry-Perot Interferometer*†

The construction and operation of a variable spacing Fabry-Perot interferometer that could be used at scanning rates up to 500 scans/sec is described. Mulitlayer interference coatings were used for reflecting surfaces in the near infrared. The high spectral luminosity of the interferometer made its use favorable in low orders for rapid-scan spectroscopy, and in high orders in combination with a grating spectrometer for greater spectral resolution.

Dynamics of self-organized χ(2) gratings in optical fibers

In this paper we report experiments on the dynamic of self-organized (chi)(2) gratings. An important observation is that the initial growth rate of (chi)(2) gratings is always linear in time. A fast transient and slow fluctuations are also observed in certain cases. The initial growth rate of the grating amplitude as a function of the irradiances of the seeding fundamental ((omega)) and second harmonic (2(omega)) beams was measured and was determined to have a power dependence on I(2(omega)) of exponent 1.48 +/- 0.2, and on I((omega)) of 0.9 +/- 0.2. A model based on selective ionization of dipolar defects due to an interference between two-photon and three-photon processes has been explored in the context of these results.