Volume 77, Issue 11, November 2006
Index of content:
- ELECTRONICS; ELECTROMAGNETIC TECHNOLOGY; MICROWAVES
77(2006); http://dx.doi.org/10.1063/1.2370733View Description Hide Description
We present a methodology for designing wideband, shot noise limited photodetectors using commercially available components and microwave engineering techniques. We use this methodology to design and construct a photodetector using wideband microwaveamplifiers and a bandwidth photodiode. Consistent with our analytic models, the photodetector exhibits linear behavior up to a level of clearance between shot noise and dark noise from at of photocurrent, reducing to of clearance at .
77(2006); http://dx.doi.org/10.1063/1.2390624View Description Hide Description
Since the interaction between the magnetic field and fluid field is complicated, the signal models of electromagnetic flowmeter under sinewave excitation cannot describe accurately the relationship among the sensor output, flow rate, and exciting signal now. The multiple regression method is adopted to build the signal models of electromagnetic flowmeter based on the experimental data in this article. The signal models not only express the action of flow rate but also reflect the effects of transformer and eddy current.
77(2006); http://dx.doi.org/10.1063/1.2356854View Description Hide Description
An electromagnetic solenoid was developed to study the effect of magnetic fields on electron thermal transport in laser plasmas. The solenoid, which is driven by a pulsed power system supplying 30 kJ, achieves magnetic fields of 13 T. The field strength was measured on the solenoid axis with a magnetic probe and optical Zeeman splitting. The measurements agree well with analytical estimates. A method for optimizing the solenoid design to achieve magnetic fields exceeding 20 T is presented.