class13
... superlattice, scattering of electrons is cut dramatically, greatly decreasing resistance Superlattices are hard to mass-produce, but the effect has been seen in three-layer devices called “spin valves” The origin of giant magnetoresistance is very different from that of regular magnetoresistance! ...
... superlattice, scattering of electrons is cut dramatically, greatly decreasing resistance Superlattices are hard to mass-produce, but the effect has been seen in three-layer devices called “spin valves” The origin of giant magnetoresistance is very different from that of regular magnetoresistance! ...
docx
... 5.1 Every set of magnet current Itot (and thus magnetic field Btot), accelerating voltage V and orbit radius r provides an independent measurement of e/m. (If the two voltages for the two positions (original and rotated) are not identical, then use the average of the two in the calculation) 5.2 Esti ...
... 5.1 Every set of magnet current Itot (and thus magnetic field Btot), accelerating voltage V and orbit radius r provides an independent measurement of e/m. (If the two voltages for the two positions (original and rotated) are not identical, then use the average of the two in the calculation) 5.2 Esti ...
Determining the electron charge to mass ratio (e/m)
... The 44 values obtained for e/m should be plotted against the accelerating voltage so that they can be distinguished by the corresponding radii of the orbits. In addition, the average value and the current most accurate value for e/m should be plotted. It should be noted that the electrons can have q ...
... The 44 values obtained for e/m should be plotted against the accelerating voltage so that they can be distinguished by the corresponding radii of the orbits. In addition, the average value and the current most accurate value for e/m should be plotted. It should be noted that the electrons can have q ...
Dual Nature of Matter and Radiation
... 2. Equation (1) shows that the photoelectrons with greater value of maximum kinetic energy will come out of the metal surface, when the frequency of incident radiation is increased. Since the equation (1) does not involve the term of intensity so the maximum kinetic energy does not depend upon the i ...
... 2. Equation (1) shows that the photoelectrons with greater value of maximum kinetic energy will come out of the metal surface, when the frequency of incident radiation is increased. Since the equation (1) does not involve the term of intensity so the maximum kinetic energy does not depend upon the i ...
Transmission Electron Microscopy -TEM
... Transmission Electron Microscopy -TEMScanning Electron Microscopy – SEM The first electron microscope was built 1932 by the German physicist Ernst Ruska, who was awarded the Nobel Prize in 1986 for its invention. He knew that electrons possess a wave aspect, so he believed he could treat them as lig ...
... Transmission Electron Microscopy -TEMScanning Electron Microscopy – SEM The first electron microscope was built 1932 by the German physicist Ernst Ruska, who was awarded the Nobel Prize in 1986 for its invention. He knew that electrons possess a wave aspect, so he believed he could treat them as lig ...
Accelerator Physics for pedestrians - Helmholtz
... Accelerator types For low accelerating voltage, e.g. for TV's or X-ray tubes, the electrostatic accelerator is the most economic. In the linear accelerator a lot of rf-cavities are put after each other such that an electron may be accelerated successively in each cavity. Linear accelerators have the ...
... Accelerator types For low accelerating voltage, e.g. for TV's or X-ray tubes, the electrostatic accelerator is the most economic. In the linear accelerator a lot of rf-cavities are put after each other such that an electron may be accelerated successively in each cavity. Linear accelerators have the ...
Electricity - WordPress.com
... Resistance is needed to control the flow of current in a circuit. Circuit resistance can be increased or decreased to control the flow of electricity ...
... Resistance is needed to control the flow of current in a circuit. Circuit resistance can be increased or decreased to control the flow of electricity ...
Photomultiplier
Photomultiplier tubes (photomultipliers or PMTs for short), members of the class of vacuum tubes, and more specifically vacuum phototubes, are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum. These detectors multiply the current produced by incident light by as much as 100 million times (i.e., 160 dB), in multiple dynode stages, enabling (for example) individual photons to be detected when the incident flux of light is very low. Unlike most vacuum tubes, they are not obsolete.The combination of high gain, low noise, high frequency response or, equivalently, ultra-fast response, and large area of collection has maintained photomultipliers an essential place in nuclear and particle physics, astronomy, medical diagnostics including blood tests, medical imaging, motion picture film scanning (telecine), radar jamming, and high-end image scanners known as drum scanners. Elements of photomultiplier technology, when integrated differently, are the basis of night vision devices.Semiconductor devices, particularly avalanche photodiodes, are alternatives to photomultipliers; however, photomultipliers are uniquely well-suited for applications requiring low-noise, high-sensitivity detection of light that is imperfectly collimated.