Hall magnetic field

Hall effect If a current (I) is passed through a conducting crystal in a direction perpendicular to that of an applied magnetic field (H), the conductor develops a potential (V) between the faces which are mutually perpendicular to both the direction of the current and the magnetic field. This is known as the Hall effect the magnitude of the potential difference is given by... 

The sensor of the third method is a Hall-effect device situated in a magnetic field of two differential arranged exiting coils. Fig. 3 shows the construction of the sensor probe. 

Due to the symmetrical construction the resulting magnetic field between the two coils is zero in y-direction, if a conductive structure is symmetrically situated in the area a (see fig. 3) in the near of the probe. A resulting field is detectable by the Hall-effect device, if there are unsym-metrics in the structure in area a. The value of the Hall voltage is proportional to the detected magnetic field. 

It is a white crystalline, brittle metal with a pinkish tinge. It occurs native. Bismuth is the most diamagnetic of all metals, and the thermal conductivity is lower than any metal, except mercury. It has a high electrical resistance, and has the highest Hall effect of any metal (i.e., greatest increase in electrical resistance when placed in a magnetic field). 

Assuming that the current in the gas is carried mostly by electrons, the induced electric field uB causes transverse electron motion (electron drift), which, being itself orthogonal to the magnetic field, induces an axial electric field, known as the Hall field, and an axial body force, F, given by... 

Now the effective conductivity ia the direction of the electric field is <7/(1 + /5 ), ie, the scalar conductivity reduced by a factor of (1 + /5 ) by the magnetic field. Also, the electric current no longer flows in the direction of the electric field a component j exists which is perpendicular to both the electric and magnetic fields. This is the Hall current. The conductivity in the direction of the Hall current is greater by a factor of P than the conductivity in the direction of the electric field. The calculation of the scalar conductivity starts from its definition ... 

The resulting overall energy balance for the plant at nominal load conditions is shown in Table 3. The primary combustor operates at 760 kPa (7.5 atm) pressure the equivalence ratio is 0.9 the heat loss is about 3.5%. The channel operates in the subsonic mode, in a peak magnetic field of 6 T. AH critical electrical and gas dynamic operating parameters of the channel are within prescribed constraints the magnetic field and electrical loading are tailored to limit the maximum axial electrical field to 2 kV/m, the transverse current density to 0.9 A/cm , and the Hall parameter to 4. The diffuser pressure recovery factor is 0.6. 

Song et al. [16] reported results relative to a four-point resistivity measurement on a large bundle of carbon nanotubes (60 um diameter and 350 tm in length between the two potential contacts). They explained their resistivity, magnetoresistance, and Hall effect results in terms of a conductor that could be modeled as a semimetal. Figures 4 (a) and (b) show the magnetic field dependence they observed on the high- and low-temperature MR, respectively. 

Figure 43. Microwave transmission in a two-mode resonator as a function of the magnetic field strength for measurement of the microwave Hall effect in FeS2 (two measurements with an offset difference).16...

Microwave power and its effect on the electrode/electrolyte interface, 439 Microwave region, Hall experiments, 453 Microwave spectroscopy, intensity modulated photo currents, 508 Microwave transients for nano crystalline desensitized cells, 514 Microwave transmission, as a function of magnetic field, 515 Minority carriers... 

Most spectrometers measure the magnetic field by a Hall effect probe consisting of a sensor mounted on one of the pole faces of the magnet. However, such estimates of the value of B inside the cavity are not sufficiently accurate to be used for g-factor determinations. There are two ways around this problem (i) measure the spectrum of a solid free radical such as dip-henylpicrylhydrazyl (DPPH), which has a well-known g-value (2.0028), at least once during acquisition of the desired spectrum or (ii) use of an NMR gaussmeter probe inserted in or near the cavity several times during the collection of the spectrum. 

The Hall Effect In the presence of an orthogonal magnetic field in the z-direction an x-directed electric current produces a y-directed gradient of the electrochemical potential. Similarly an x-directed thermal gradient produces a y-directed gradient of the electrochemical potential, known as the Nernst effect. 

Soule D. Magnetic field dependence of the hall effect and magnetoresistance in graphite single crystals. Physical Review. 1958 112(3) 698-707. 

The Hall effect, an electric field perpendicular to both the impressed current flow and to the applied magnetic field, gives information about the mobility of the charge carriers as well as their sign. The Hall coefficient RH - Ey/JxHe is proportional to the reciprocal of the carrier density. The Hall coefficient is negative for electron charge carriers. 

The effect increased with penetration of the wave front into the electric field. Addition of a magnetic field decreased the total current across the slug, by about 40% when the j x B force was in the direction of wave propagation, but by about 25% when the force was against this direction. There was no effect on the wave speed unless the j x B force was against the flow, in which case the wave speed was lowered by up to 10% on account of an increase of turbulence in the boundary layer. The changes in wave structure observed were attributed to the "Hall Effect ... 

The Hall Effect, in magnetohydrodynamics (MHD), rotates the current vector away from the direction of the electric field and generally reduces the level of the force that the magnetic field exerts on the flow. It is usually measured by the parameter cor, where co = eB/m is the angular velocity of the electron orbits around the field lines, and r is the mean time between scattering collisions for the electrons. The form of Ohm s law which accounts for the Hall Effect (See Ref 2a) is ... 

The Hall effect in the temperature range where conduction is by variable-range hopping is not well understood. Evidence from the early work by Fritzsche is discussed by Shklovksii and Efros (1984), who come to the conclusion that the Hall mobility must be small. Hopkins et al (1989) have investigated the behaviour of heavily doped Ge Sb, pushed into the non-metallic regime by magnetic fields up to 7 T, at temperatures down to 100 mK. Below 1 K the... 

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