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We present an innovative technique which allows the simultaneous measurement of the dielectric constant of a material at many frequencies, spanning a four orders of magnitude range chosen between 10 --2 Hz and 10 4 Hz. The sensitivity and accuracy are comparable to those obtained using standard single frequency techniques. The technique is based on three new and simple features: a) the precise real time correction of the amplication of a current amplier; b) the specic shape of the excitation signal and its frequency spectrum; and c) the precise synchronization between the generation of the excitation signal and the acquisition of the dielectric response signal. This technique is useful in the case of relatively fast dynamical measurements when the knowledge of the time evolution of the dielectric constant is needed.
Radio-frequency reflectometry of nanodevices requires careful separation of signal quadratures to distinguish dissipative and dispersive contributions to the device impedance. A tunable phase shifter for this purpose is described and characterized. T
We have developed a system for contactless measurement of nonlinear conductivity in the radio-frequency band, and over a wide temperature range. A non-resonant circuit is used to electrically excite the sample, and the induced signal is detected by a
In 2006, a final result of a measurement of the gravitational constant $G$ performed by researchers at the University of Zurich was published. A value of $G=6.674,252(122)times 10^{-11},mbox{m}^3,mbox{kg}^{-1},mbox{s}^{-2}$ was obtained after an expe
Lab::Measurement is a framework for test and measurement automatization using Perl 5. While primarily developed with applications in mesoscopic physics in mind, it is widely adaptable. Internally, a layer model is implemented. Communication protocols
This paper presents the design and fabrication of batch-processed cantilever probes with electrical shielding for scanning microwave impedance microscopy. The diameter of the tip apex, which defines the electrical resolution, is less than 50 nm. The