The T 0.58(4) power law dependence of L with temperature indicates that the weak antilocalization is two-dimensional. My understanding is that for weak localization the presence of weak disorder leads to some electron paths interfering destructively since there is an equal probability for it to take one complete "circle" in one direction to taking the same path in the opposite direction so the phases cancel, resulting in fewer electrons diffusing all the way through the material and hence we would measure an increase in resistivity. (d) The phase coherence length of carriers in LaCuSb 2 as extracted by fitting the low-field magnetoresistance curves of LaCuSb 2 to the HLN theory for weak antilocalization. The last bit is the part I don't get, I would have thought that if the two paths interfere destructively then surely the resistivity would increase? What does the spin-orbit coupling change, since that seems to be the only difference between antilocalization and localization which seem to result in two opposite effects on the resistivity. Because of this, the two paths any loop interfere destructively which leads to a lower net resistivity. The weak antilocalization always dominates the magnetoconductivity near zero field, thus gives one of the transport signatures for Weyl semimetals. The spin of the carrier rotates as it goes around a self-intersecting path, and the direction of this rotation is opposite for the two directions about the loop. The phase coherence lengths at different temperatures are determined by fitting observed low-field weak antilocalization (WAL) effect with modified Hikami-Larkin-Nagaoka equation. In a system with spin-orbit coupling the spin of a carrier is coupled to its momentum. The temperature dependence of the coherence length derived from the weak antilocalization effect using the Hikami-Larkin-Nagaoka model is consistent with that from the universal conductance fluctuations theory.On Wikipedia (pretty much the only place I can find an explanation of what weak anti-localization actually is) it is explained as: The obtained temperature dependence of phase coherence length and the fluctuation amplitude indicates that the transport of electrons shows 2-dimensional characteristics originating from the surface states. One of the most interesting questions in weak localization is the influence of spin-orbit coupling. Therefore the coherent backscattering increases with decreasing temperature and in parallel the resistance increases. The phase coherence length was obtained from the fluctuation pattern of the magnetoresistance below 40 K using universal conductance fluctuation theory. At high temperature the scattered waves loose their phase coherence due to inelastic processes. The temperature dependent resistance and magnetoresistance of Bi nanowires were investigated. The temperature dependence of the coherence length derived from the weak antilocalization effect using the Hikami-Larkin-Nagaoka model is consistent with that from the universal conductance fluctuations theory.ĪB - We present the low temperature transport properties of an individual single-crystalline Bi nanowire grown by the on-film formation of nanowire method. In that case, in a weakly disordered system, the quantum diffusive regime, occurs, and the electrons can move. The phase coherence length was obtained from the fluctuation pattern of the magnetoresistance below 40 K using universal conductance fluctuation theory. As the temperature of a system is decreased, the phase coherence length, l, which defines the average distance an electron can travel until its phase is randomized, can increase and become larger than the elastic mean free path, l e. We find that the magnetotransport data agree well with the Hikami-Larkin-Nagaoka theory. (Phys Rev B 100:125162, 2019), which assumes infinite phase coherence length (l ) and a zero spin-orbit scattering length (l SO), the present framework is more general, covering high T and the intermediate spin-orbit coupling strength. N2 - We present the low temperature transport properties of an individual single-crystalline Bi nanowire grown by the on-film formation of nanowire method. We observe a gate-tunable weak antilocalization behavior at lower magnetic field B, which shows a transition to weak localization at higher B region. Compared to the previous approach Vu et al. In particular, the crossover from weak antilocalization to weak localization in the bulk states is observed in the parallel magnetic field measurements up to 50. T1 - Weak antilocalization and conductance fluctuation in a single crystalline Bi nanowire Magnetoconductivity measurements of SnTe films reveal a coexistence of weak antilocalization, consistent with topologically non-trivial states, and weak localization, consistent with trivial states from the bulk.
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