Iouri Solomatine

Tunable Optical Frequency Comb with a Crystalline Whispering Gallery Mode Resonator

We report on the experimental demonstration of a tunable monolithic optical frequency comb generator. The device is based on four-wave mixing in a crystalline calcium fluoride whispering gallery mode resonator. The frequency spacing of the comb is given by an integer number of the free spectral range of the resonator. We select the desired number by tuning the frequency of the pumping laser with respect to the corresponding resonator mode. We also observe a rich variety of optical combs and high-frequency hyperparametric oscillation, depending on the experimental conditions. A potential application of the comb for generating tunable narrow band frequency microwave signals is demonstrated.

Characterization of phenanthrenequinone-doped poly(methyl methacrylate) for holographic memory

The holographic recording characteristics of phenanthrenequinone- (PQ-) doped poly(methyl methacrylate) are investigated. The exposure sensitivity is characterized for single-hologram recording, and the M/# is measured for samples as thick as 3 mm. Optically induced birefringence is observed in this material.

Holographic recording in a photopolymer by optically induced detachment of chromophores

We demonstrate holographic recording in a new photopolymer system. The recording material is created by copolymerization of an optically inert monomer, methyl methacrylate, and a second monomer that is optically sensitive. On exposure of the recording material to light, a portion of the optically sensitive component detaches from the polymer matrix and causes hologram amplification through diffusion of the free molecules. We measured postrecording grating amplifications as high as 170% by this process. The recorded holograms are persistent at room temperature under continuous illumination at the recording wavelength.

Comparison of the recording dynamics of phenanthrenequinone-doped poly(methyl methacrylate) materials

A comparative analysis of phenanthrenequinone-doped poly(methyl methacrylate) materials fabricated at California Institute of Technology and National Chiao Tung University is performed in order to understand the differences exhibited in their recording and baking dynamics.

Crystal quartz optical whispering-gallery resonators

A quality factor exceeding 5x10(9) is obtained in whispering-gallery mode (WGM) resonators fabricated of crystalline quartz. We observe significant electrical tunability of WGMs in x-cut resonators and demonstrate an electro-optic modulator with a submegahertz passband at 12 GHz. We discuss other photonics applications of the crystal quartz WGM resonators in narrowband agile tunable filters, compact narrow linewidth lasers, and microwave and millimeter wave oscillators.

Holographic data storage in phenanthrenequinone-doped PMMA

Phenanthrenequinone (PQ)-doped poly(methyl methacrylate) (PMMA) is a photopolymer holographic recording material that can be made in large thicknesses and does not exhibit any shrinkage. Hologram are made permanent by a post-recording diffusion amplification process. PQ-doped PMMA thus exhibits may properties which make it an ideal candidate as a high- density read-only holographic data storage medium. Recently we reported the holographic recording characteristics of phenanthrenequinone (PQ) doped PMMA. We now demonstrate the holographic storage of binary data in this material. Shift multiplexing is used to store multiple holographic data pages in millimeter thick material samples. Each data page consists of a random array of binary 40 micron pixels. Recording is performed near the Fourier transform plane of the data mask, allowing high bit-densities to be achieve.d The signal to noise ratio of stored data pages is used as an indication of hologram quality and data integrity. Bit density limitations are discussed with respect to the current performance of the recording material.

Derivation and measurement of the M/# in spectral hole burning media

We demonstrate 10 plane wave holograms angularly multiplexed at one frequency channel in spectral hole burning medium. We show that the M/# is still a valid system metric and the measured M/# in one frequency channel is about 0.01.

A birefringent polymer for holographic recording

Polymer based holographic recording materials are promising media for data storage applications. Among these, PMMA based materials have a long history. We present new results with one such material, consisting of PMMA with phenanthrenequinone (PQ) molecules. Specifically, the suitability of this material for holographic data storage will be discussed as well as applications to optical correlation systems.