Network Synthesis

Contains reports on two research projects

Shot noise in mesoscopic systems

This is a review of shot noise, the time-dependent fluctuations in the electrical current due to the discreteness of the electron charge, in small conductors. The shot-noise power can be smaller than that of a Poisson process as a result of correlations in the electron transmission imposed by the Pauli principle. This suppression takes on simple universal values in a symmetric double-barrier junction (suppression factor 1/2), a disordered metal (factor 1/3), and a chaotic cavity (factor 1/4). Loss of phase coherence has no effect on this shot-noise suppression, while thermalization of the electrons due to electron-electron scattering increases the shot noise slightly. Sub-Poissonian shot noise has been observed experimentally. So far unobserved phenomena involve the interplay of shot noise with the Aharonov-Bohm effect, Andreev reflection, and the fractional quantum Hall effect.Comment: 37 pages, Latex, 10 figures (eps). To be published in "Mesoscopic Electron Transport," edited by L. P. Kouwenhoven, G. Schoen, and L. L. Sohn, NATO ASI Series E (Kluwer Academic Publishing, Dordrecht

MMICS in the USA-Status and modeling issues

Significant developments in microwave device modeling and monolithic microwave integrated circuit (MMIC) technology have transpired in the USA (during the last 3-4 years. These developments have been broad-based, encompassing both materials and device technology in a manufacturing environment as well as component and device modeling, off- and on-wafer testing, CAD software development and packaging among others. Much of the impetus for this progress has been the substantial funding under the Microwave- and Millimeter-wave Integrated Circuit (MIMIC) program managed by the Defense Advanced Research Projects Agency (DARPA) and administered by the Tri-Service Agencies. Other important developments, outside of this effort, also have taken place, especially in HBT device and circuit design, as well as in civilian applications of MMICs such as GPS and wireless cable. This presentation is a status review of some of the highlights in MMIC development in the USA during the last several years both within and outside of the MIMIC program. Also to be addressed are the major modeling issues that need be resolved to make possible high performance, low cost MMICs a reality