Zero magnetic field

EPR absorption has been detected from zero magnetic field up to fields as high as 30 T corresponding to a... 

In Fig.. I we present the temperature dependence of the conductance for one of the CNTs, measured by means of a three-probe technique, in respectively zero magnetic field, 7 T and 14 T. The zero-field results showed a logarithmic decrease of the conductance at higher temperature, followed by a saturation of the conductance at very low temperature. At zero magnetic field the saturation occurs at a critical temperature, = 0.2 K, which shifts to higher temperatures in the presence of a magnetic field. 

Notice that if the molecule has axial symmetry, Dxx = Dyy so that E=0. If the molecule has octahedral symmetry, Dxx = Dyy = Dzz so that D = E=0. Thus the appearance of a zero-field splitting into two or three levels tells the spectroscopist something about the symmetry of the molecule. It is possible, of course, to do spectroscopy on these energy levels at zero magnetic field. Our concern here is the effect of zero-field splitting on the ESR spectrum where a magnetic field is applied. 

Bramley, R. and Strach, S.J. 1983. Electron paramagnetic resonance spectroscopy at zero magnetic field. Chemical Reviews 83 49-82. 

Around 1 mK, the solid 3He, in zero magnetic field, undergoes a nuclear ordering its entropy falls by an order of magnitude (see Fig. 7.2) and the cooling power of the process... 

In Table 8.11, the approximate transition temperature of some elements in zero magnetic field and critical fields are reported [31]. 

Fig. 9.11. Capacitance (minus 630 pF) of a capacitive glass thermometer as a function of temperature. The data points were obtained at excitation frequencies of 1.0 and 4.7 kHz at zero magnetic field (x) and...

W.M. Becker, Band Structure and Optical Properties of Wide-Gap A 1MnJ[BVI Alloys at Zero Magnetic Field... 

The impact of Equation 10.14 in the treatment of spin-polarized systems is in two directions on the one hand, it allows the inclusion of external magnetic field effects in the description of /V-electron systems on the other hand, when the limit of zero magnetic field is imposed, the formalism becomes useful for /V-electron systems having spin-polarized ground state in the absence of a external magnetic field. This... 

Anodization of Si in HF under an applied magnetic field produces an enhancement of the PL efficiency at RT, accompanied by an enhanced porosity compared to PS samples prepared without an applied field. The degree of polarization of the emitted PL is reduced for field-assisted preparation [Na3]. At low temperatures (4.2 K), the Stokes shift and the decay time of the PL are found to be increased, if compared to PS formed under zero magnetic field. This has been interpreted as Zeeman splitting of the spin-triplet exciton states. It indicates that the ground state of the luminescing silicon crystallite is a triplet state [Kol3]. 

The new techniques of phosphorescence-microwave multiplet resonance spectroscopy with optical detection have been reviewed by El-Sayed and Kwiram Such exciting experiments as the optical detection on electron-nuclear double resonance (ENDOR) and of electron-electron double resonance (EEDOR) in zero magnetic field have been achieved, and it is certain that much detailed knowledge concerning the phosphorescent states will evolve from this field. 

The symbol xso denotes the electron spin relaxation time at zero magnetic field, where Ti = and is another correlation time, associated with distortions of the paramagnetic complex caused by molecular collisions. 

Fig. 14. The outer-sphere relaxivity at zero magnetic field as a function of relative diffusion coefficient for S = 1. Reproduced with permission from Kruk, D. Nilsson, T. Kowalewski, J. Mol. Phys. 2001, 99,1435-1445. Copyright 2001 Taylor and Francis Ltd (http //www.tandf.co.uk/journals/tf/00268976.html).

S5 — Sjv)r—o = yT- The behaviour of y in the superconducting state is different from that of the normal state y is a linear function of temperature in the normal state but its temperature dependence is exponential in the superconducting state. The superconducting transition at zero magnetic field is a second-order phase transition since there is discontinuity in specific heat but no latent heat change. 

Fig. 14. Temperature dependence of the resistivity p at zero magnetic field for Gal rMnJtAs films with x = 0.015-0.071. Samples with x = 0.035-0.053 exhibit metallic behavior. The inset shows an expanded view...

Fig. 62. Configuration of magnetisation and magnetic moment in the sandwich TbCo/NdCo/TbCo film in zero magnetic field (a) and during the (de)magnetisation processes (b-e).

CRITICAL TEMPERATURE. 1. This term is most commonly used to denote the maximum temperature at which a gas (or vapor) may be liquefied by application of pressure alone. Above this temperature Ihe substance exists only as a gas. 2. The critical temperature of a superconducting transition takes place in zero magnetic field. 

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