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We present experimental and modeling results investigating rare earth-doped (Er and Yb) YAG-derived silica fibers (RYDF) as candidates for use in high-power narrow-linewidth fiber lasers. Fabrication of the RYDFs via a rod-in-tube method, starting from crystalline YAG, and its transformation to the amorphous state is described. Stimulated Brillouin scattering (SBS) suppression results from material properties that cooperate to yield a low Brillouin gain coefficient (BGC), namely reduced photoelastic constant and increased acoustic velocity, mass density, and Brillouin spectral width relative to silica. We find typical BGC values for large-mode-area RYDFs to be around 0.5×10-11m/W. Utilizing a materials model, these results are extrapolated to compositionally-design further reductions to the BGC, including introducing other co-dopants to the mixture. Finally, we focus on the Yb-doped RYDF (YYDF) and show that it is a good candidate for use in kW-class narrow-linewidth fiber lasers via spectroscopy and amplifier experiments. The RYDFs are found to be very similar to conventional aluminosilicate fibers. We also find that YYDFs offer improved compatibility with phase modulating the laser for further increases in the SBS threshold. Using novel fiber fabrication methods with less-common and low-silica materials can lead to promising glass recipes with ultra-low intrinsic BGCs.

Calcium aluminate glass has a refractive index less than 1 at 10.6 μm, and therefore it is a good candidate for a hollow fiber for the transmission of CO_2 laser energy. We have drawn hollow calcium aluminate glass fibers with inner diameters ranging from 380 to 500 μm. The loss for our 500-μm inner-diameter hollow glass fibers measured at 10.6 μm is 8.6 dB/m.

In this Letter, the fabrication and characterization of a microsphere resonator from the semiconductor germanium is demonstrated. Whispering gallery modes are excited in a 46 μm diameter germanium microsphere resonator using evanescent coupling from a tapered silica optical fiber with a waist diameter of 2 μm. Resonances with Q factors as high as 3.8×10^4 at wavelengths near 2 μm are observed. Because of their ultrahigh optical nonlinearities and extremely broad transparency window, germanium microsphere resonators offer the potential for optical processing devices, in particular at long wavelengths, such as around 2 μm.

Reports on the indictment and arrest of Shaun A. Walker, Travis D. Massey, and Eric G. Egbert on June 9, 2006, after being charged with federal civil rights violations for barroom assaults on a Mexican immigrant and an American Indian. Allegations of the Anti-Defamation League against the neo-Nazi group National Alliance; Results of the investigation conducted on the case.

If we could eliminate the phenomenon of stimulated Brillouin scattering (SBS), we could create pulsed laser sources for spectroscopic and coherent lidar applications, as well as multi-kW narrow-linewidth fiber laser sources for coherently phased laser arrays. With that in mind, we used a novel fiber fabrication method known as the moltencore method to realize a new class of optical fibers: all-glass optical fibers free from the effects of SBS.

There are very strong interests for power scaling in high power fiber lasers for a wide range of applications in medical, industry, defense and science. In many of these lasers, fiber nonlinearities are the main limits to further scaling. Although numerous specific techniques have studied for the suppression of the wide range of nonlinearities, the fundamental solution is scaling mode areas in fibers while maintaining sufficient single mode operation. Here the key problem is that more modes are supported once physical dimensions of waveguides are increased. There are two basic approaches, lower refractive index contrast to counter the increase of waveguide dimension or/and introduction of additional losses to suppress higher order modes. Lower index contrast leads to weak waveguides, resulting in fibers no longer being coil-able. Our research has been focused on designs for significant higher mode suppression. In conventional waveguides, modes are increasingly guided in the center of the waveguides when waveguide dimensions are increased. It is hard to couple the modes out to suppress them. This severely limits the scalability of all designs based conventional fibers. In an all-solid photonic bandgap fiber, modes are guided due to anti-resonance of cladding photonic crystal lattice. This leads strongly mode-dependent guidance. Our theoretical study has shown that it can have some of the highest differential mode losses among all designs with equivalent mode areas. Our design and experimental works have shown the potential of this approach for all-glass fibers with >50m core which can be coiled for high power applications.

The article reports on the intention by antiquities dealer Carl Crites, who was forced to surrender five truckloads of American Indian relics to federal agents, to settle charges of digging up a grave and plundering artifacts from federal lands.

The article reports on the agreement signed by various groups including federal and state agencies, conservation and archaeology groups, and tribal leaders on January 5, 2010 to protect the Nine Mile Canyon that contains artworks in Utah. It states that the pact calls for road work to remove dust that can erode the rock art panels of the canyon. It also obliges the Bureau of Land Management (BLM) to protect the entire canyon. Moreover, Bill Barrett Corp. waits for the approval of the work.

The article reports on the supposition of Larry Echo Hawk, a law professor at the Brigham Young University, over the status of Tribes to reclaim the artifacts being seized by the state government of Utah in its sweeping prosecution of theft and trafficking. According to Echo Halk, the tribe should have the first priority to recover the items. Moreover, he added that items, such as sacred and burial objects, are supposed to go back to their rightful culture.

The article reports on the transfer of custody of the Range Creek Canyon from the Utah Division of Wildlife Resources (DWR) to the archaeologists of the University of Utah. Duncan Metcalfe, chief curator of the Utah Museum of Natural History says that such transfer allows them to focus on natural history research as well as on the archaeology of the canyon. Moreover, DWR habitat section chief Mike Canning states that wildlife habitat and public access to Range Creek will be maintained.

The article reports on the possible increase on the number of suspects for the biggest artifact looting case in the U.S. It says that 25 people involved in the case have already been charged for stealing artifacts from federal as well as tribal lands in Four Corners region. It notes that federal authorities target wealthy private collectors who fuel the underground markets. It cites that two of the defendants have committed suicide while one artifact dealer expects a visit from federal agents.

The article reports that the proposed coal plant in Navajo Nation, Arizona has prompted fierce debate pitting the economic windfall against environmental concerns and traditional culture on the reservation, rich with natural gas, uranium and low sulfur coal. Others say the $3 billion Desert Rock Energy Facility could invigorate the lagging economy of the Navajo Nation.

The article discusses a lawsuit filed by the Skull Valley band of Goshute and Private Fuel Storage (PFS), over claims that the U.S. Interior Department killed a nuclear waste dumping project because of political pressures and not on merits. The project involved the tribe allowing PFS to store nuclear waste on its reservation in Utah's west desert, in exchange for $200,000 a year and job opportunities for tribal members.

The article reviews the Web site www.footnote.com which displays historical documents.

The article reports on the rejection of a plan by the U.S. Interior Department to create a nuclear waste stockpile on the Skull Valley Reservation in Utah. The agency vetoed a lease Goshute tribal leaders approved for the stockpile and also refused to yield federal land for a transfer station. A spokeswoman for Private Fuel Storage, a group of nuclear-power utilities which won a license from the Nuclear Regulatory Commission, suggested it was premature to call it dead.

Reports on the decision of Utah's congressional delegation to protect the Cedar Mountains from nuclear waste. Designation of the mountain as a wilderness protection area; Purpose of the Wilderness Act of 1964; Comments from tribal Chief Leon Bear on the issue.