Dennis W. Garvey

Generation of 11-fs pulses from a self-mode-locked Ti:sapphire laser

By optimizing the intracavity dispersion compensation in a self-mode-locked Ti:sapphire laser, we have generated pulses of 10.95-fs duration. Dispersion within the laser cavity is reduced by use of a short 4.5-mm highly doped Ti:sapphire crystal and fused-silica prisms. The output from the laser has an average power of as much as 500 mW, with a wavelength centered at 780 nm and a bandwidth of 62 nm. Our results demonstrate that the exceptionally broad bandwidth of Ti:sapphire can be utilized to generate pulses that, to our knowledge, are shorter than has been possible with any other type of laser material to date.

Single-mode nonlinear-optical polymer fibers

We report on the successful demonstration of a single-mode polymer-optical fiber with an 8-µm-diameter nonlinear-optical core composed of a dye-chromophore-doped polymer. Both solid-solution cores and copolymer cores were successfully fabricated. Using an imaging system, we show that the far-field transverse light pattern is that of a single-mode guide. We find that the loss at 1064 nm for the single-mode fiber is approximately 0.2 dB/cm and that it preserves polarization to better than 99.8%/cm.

Fabrication and characterization of single-mode electro-optic polymer optical fiber

We report on what we believe is the first demonstration of single-mode polymer optical fiber with embedded electrodes. We show that the electrodes can be used to pole the dye-doped core and to electro-optically phase modulate the light in the waveguide.

All-optical devices in polymer optical fiber

Abstract We report on polymer optical fiber devices for sensors, optical switches/logic, and optical actuators. In this paper, we give a brief overview of polymer fibers, discuss recent all-optical switching results, and describe how an optical sensor and actuator can be built into a single fiber device. Future technologies that are made possible with such optical devices and photomechanical mechanisms are also discussed.

Sagnac interferometric intensity-dependent refractive-index measurements of polymer optical fiber

We have applied a new modified Sagnac interferometric technique to measure the real part of the intensitydependent refractive index of a single-mode polymer optical fiber. For a 0.1% by weight squaraine dye in a poly(methyl methacrylate) core, Re([chi((3))1111]) is 12(+/-7) x 10(-13) cm(3)/erg at lambda = 1064 nm. We discuss the effect of these measurements on all-optical devices.

CHARACTERIZATION OF SINGLE-MODE POLYMER OPTICAL FIBER AND ELECTROOPTIC FIBER DEVICES

Abstract Polymer optical fiber can be used to make a wide variety of devices such as transmission systems, optical sensors, optical switches/logic, and optical actuators. In this paper, we give a brief overview of devices that are made in fiber and discuss the first demonstration of single-mode polymer optical fiber with embedded electrodes. Future technologies that are made possible with optics are also discussed.

Spyrobenzopyran-doped core PMMA fibers

Cylindrical PMMA filters with core regions doped with spirobenzopyran molecules have been fabricated. Spirobenzopyran is a photochromic molecule with two forms: spiropyran and merocyanine. In the fibers, one state could be reverted to the other either by a photo-initiated reaction or by thermal excitation. The fluorescence from the merocyanine form could be generated by exciting the core with a 543nm laser. For spirobenzopyran, higher temperatures favor the reaction form spiropyran form to merocyanine form, hence as temperature increases the merocyanine from concentration in the core increase causing the fluorescence intensity to increase. It was observed that the fluorescence increased fairly linearly over a certain range and started rolling off as the temperature approached to 60 degrees C. Refractive index and material dispersion characteristics of SP/PMMA was also measured. Fluorescence generation in the core by two-photon absorption from 40 ps pulses at 1064 nm has been demonstrated. The energy of the pulses was 1.8 uJ, which gave a peak intensity of 5GW/cm2 in 33um core. A portion of the emitted fluorescence was guided to the end of the fiber and a portion of it escaped the cladding and radiated into the air.

Characterization of the switching properties of a singlemode polymer optical fiber

We report on the all-optical switching characteristics of a single-mode polymer optical fiber with a squaraine dye-doped poly(methyl)methacrylate core using a Sagnac interferometer.

Nonlinear optics in polymer optical fibers

We report on a method developed for characterization the third order optical nonlinearity of singlemode polymer optical fiber. The Sagnac homodyning method yields values for both the real and imaginary components of (chi) (3) from a single measurement. The method also allows for the separation of the effects due to nonlinear mechanisms having response times on the order of milliseconds or slower. The 10micrometers core of the characterized fiber was doped with 0.15 percent by weight of the squaraine HSQ. The real component of the nonlinearity was determined to be Re((chi) (3) equals -9.8 +/- 2.5 X 10-12 esu, and the imaginary component Im((chi) (3) equals 5.5 +/- 0.3 X 10-12 esu.

Single-mode electro-optic polymer optical fiber

We have made single mode polymer optical fiber with embedded electrodes. The electrodes can be used to pole the dye-doped core and electro-optic phase modulation of light in the waveguide has been demonstrated. The method of lead attachment to the electrodes is discussed and the optical/electrical properties of device structures characterized.