Trajectories for the 1976-1980 grand tour opportunities. Volume 1 - Graphic and summary trajectory data

Trajectories for 1976 to 1980 Grand Tour

An observation of spin-valve effects in a semiconductor field effect transistor: a novel spintronic device

We present the first spintronic semiconductor field effect transistor. The injector and collector contacts of this device were made from magnetic permalloy thin films with different coercive fields so that they could be magnetized either parallel or antiparallel to each other in different applied magnetic fields. The conducting medium was a two dimensional electron gas (2DEG) formed in an AlSb/InAs quantum well. Data from this device suggest that its resistance is controlled by two different types of spin-valve effect: the first occurring at the ferromagnet-2DEG interfaces; and the second occuring in direct propagation between contacts.Comment: 4 pages, 2 figure

Wave Packet Echoes in the Motion of Trapped Atoms

We experimentally demonstrate and systematically study the stimulated revival (echo) of motional wave packet oscillations. For this purpose, we prepare wave packets in an optical lattice by non-adiabatically shifting the potential and stimulate their reoccurence by a second shift after a variable time delay. This technique, analogous to spin echoes, enables one even in the presence of strong dephasing to determine the coherence time of the wave packets. We find that for strongly bound atoms it is comparable to the cooling time and much longer than the inverse of the photon scattering rate

Farmer\u27s Market Consumers: Is Local or Organic Important?

Consumer demand for alternative foods, such as organic and local products, increased dramatically in the last decade in the United States. Sales of organic products in the U.S. reached $21.1 billion in 2008, representing three percent of total food sales, and are projected to climb to$23.0 billion in 2009 (USDA-ERS 2009). Fresh produce –i.e. fresh fruits and vegetables­–have long stood as the top-selling organic products in the U.S. and accounted for 37 percent of organic food sales in 2008 (USDA-ERS 2009), or approximately $7.8 billion. This may be due in part to the fact that the adoption of organic practices has been highest among fruit and vegetable producers (Greene et al. 2009) while production of organic grains–inputs for both processed organic products and organic meats–has been outpaced by demand. Additionally, the Hartman Group estimates that 69 percent of U.S. households purchased one or more organic products in 2008, a figure that showcases the increasingly mainstream nature of organic products (Greene et al. 2009, p.3)