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This work presents a novel method to introduce a sustainable biaxial tensile strain larger than 1% in a thin Ge membrane using a stressor layer integrated on a Si substrate. Raman spectroscopy confirms 1.13% strain and photoluminescence shows a direct band gap reduction of 100meV with enhanced light emission efficiency. Simulation results predict that a combination of 1.1% strain and heavy n(+) doping reduces the required injected carrier density for population inversion by over a factor of 60. We also present the first highly strained Ge photodetector, showing an excellent responsivity well beyond 1.6um.

We have detected the 626 GHz / = 1-> 0 transition of hydrogen chloride (H 35 C1) in absorption against the dust continuum emission of the molecular cloud Sagittarius B2. The observed line shape is consistent with the blending of the three hyperfine components of this transition by the velocity profile of Sgr B2 observed in other species. The apparent optical depth of the line is T « 1, and the minimum HCl column density is 1.6 X 10 14 cm" 2. A detailed radiative transfer model was constructed which includes collisional and radiative excitation, absorption and emission by dust, and the radial variation of temperature and density. Good agreement between the model and the data is obtained for HC1/H 2 ~ 1.1 X 10~9. Comparison of this result to chemical models indicates that the depletion factor of gas-phase chlorine is between 50-180 in the molecular envelope surrounding the SgrB2(N) and (M) dust cores.

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Individuals with Parkinson's disease (PD) often require nursing home care, where access to neurologists is limited. Telemedicine uses information and communication technologies to provide health care to individuals who are geographically separate from providers. We present a video report of a nursing home resident with PD who received telemedicine visits over 8 months from a movement disorders specialist. The visits resulted in improvements in motor and cognitive symptoms and suggest that telemedicine may be useful for delivering care to this population.