![]() Signatures of weak anti-localization are observed near. The temperature dependence of the dephasing rate is consistent with the Nyquist mechanism. Phase coherence time and zero-field spin-splitting are extracted following Golub’s model L. The presence of a spin-orbit interaction manifested as weak antilocalization in the p-type epilayer suggests that these structures could be developed for use in spintronic devices such as the spin-FET, where significant spin lifetimes would be important for efficient device operation. The contribution of 2D and 3D weak antilocalization are investigated by utilizing the Tkachov-Hankiewicz model. At weak magnetic fields, the weak antilocalization effect in the ballistic regime is observed. By varying the tilt angle of the magnetic field with respect to the layer surface information on the anisotropy of is gained. In the p-type device, the measured spin diffusion length does not change over the range of temperatures for which weak antilocalization can be observed. The phase-coherence length as a figure-of-merit for phase-coherent transport was extracted by analyzing the weak antilocalization effect. We discuss the effects of two-carrier transport, weak localization, weak antilocalization, and strong localization for graphene devices of various. The decay of the phase coherence length with temperature is found to obey the same power law of lϕ ∝ Tc, where c = −0.68 ± 0.03, for each device, in spite of the clear differences in the nature of the conduction. 1 in the massless limit and 0 in the large-mass limit. Information on phase-coherence can be obtained by analyzing transport phenomena such as weak (anti)localization and universal conductance fluctuations in structures of the according length scale 24. We obtain phase coherence lengths as large as 325 nm in the highly doped n-type device, presenting possible applications in quantum technologies. (a) The weak antilocalization phase coherence length ( AL, red and magenta) and the weak localization phase coherence length ( L, blue and cyan) as a function of Berry phase for weak ( so 10 000 nm) and strong ( so 300 nm) spin-orbit scattering. When B depends 0, qi on the is proportional phase to coherence. From fits to these data using the Hikami-Larkin-Nagaoka model, the phase coherence length of each device is extracted, as well as the spin diffusion length of the p-type device. The weak antilocalization has been widely observed in three-dimensional Dirac and. A careful analysis revealed a relatively high phase coherence length (58nm at 1.78K) for a PLD grown film. a Pseudospin-momentum locking induces a phase shift for the two electron trajectories (antilocalization). We carried out extensive magneto-transport studies of these films and found that they exhibit two dimensional weak antilocalization behaviour. Download scientific diagram Weak (anti)localization magnetoresistance at various temperatures for a 43 nm wide wire (quasi-1D, top) and a 500 nm wide wire (quasi-2D, bottom), with fits to Eqs. Both n- and p-type devices show quantum corrections to the conductivity in an applied magnetic field, with n-type devices displaying weak localization and p-type devices showing weak antilocalization. The films were found to be of good quality. The behaviour for S1 and S2 were found to be similar.The magnetoresistance of 50 nm thick epilayers of doped germanium is measured at a range of temperatures down to 1.6 K. ![]() Figure 4c and d show the temperature dependence of mobility and carrier density for S0. Magnetoresistance measurements performed on a reactively DC-sputtered thin film at low temperatures (T < 8 K) suggest a 2D weak antilocalization. 4b and the parameters extracted from the fit to the data for all the films are given in Table 1. ![]()
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