John Tolle

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From November 1981 to April 1983, OCLC's Office of Research has been conducting research into online public access catalogs (OPACs). This project has been funded in part by the Council on Library Resources, Inc. as an attempt to provide new insight into the use of online catalogs by obtaining information which may serve as input for better system design of(More)
GeSn/Ge heterostructure microdisks integrated on Si were fabricated. The quality of material grown by CVD was investigated and the photoluminescence spectrum was measured using a Ti:Sapphire laser as an excitation source under variable pump powers.
Temperature dependent spectral response and detectivity of GeSn photoconductors on silicon for short wave infrared detection, " Opt. Temperature dependent spectral detectivity to 2.4 μm and peak responsivity of 1.63 A/W for a Ge0. Competition of optical transitions between direct and indirect bandgaps in Ge1-xSnx, " Appl. Room-temperature(More)
Photoluminescence (PL) from Ge<sub>1-x</sub>Sn<sub>x</sub> grown on Si by CVD was investigated for Sn composition of 0.9, 3.2, 6, and 7%, respectively. The direct and indirect band transitions were analyzed at different temperatures.
Thin film Ge<sub>1-x</sub>Sn<sub>x</sub> photodetectors fabricated on Si using a CMOS compatible process had responsivities at 1.55 &#x03BC;m of 6.59, 1.49, 2.63, and 0.84 mA/W for 0.9, 2.57, 3.2, and 7.0 % Sn. Spectral response for a Ge<sub>0.93</sub>Sn<sub>0.07</sub> photodetector had extended infrared response out to 2.2 &#x03BC;m.
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