Spin-orbit effects in a GaAs quantum dot in a parallel magnetic field.

摘要: We analyze the effects of spin-orbit coupling on fluctuations conductance a quantum dot fabricated in GaAs heterostructure. Counterintuitively we argue that may become important presence large parallel magnetic field Bk, even if they are negligible for Bk 0. This should be manifest level repulsion closed dot, and reduced dots with small number open channels each lead, Bk. Our picture is consistent experimental observations Folk et al. Recent experiments by [1] studied statistics g through heterostructure an applied plane sample. In largest studied, application Bjj was observed to reduce variance fluctuations, varg, factor roughly 4, contrast reduction 2, which originally expected. As noted al., extra might understood if, some reason, increased While naively one expect align electron spin such way makes less effective, this Letter confinement structure leads opposite effect. effect could well explain Ref. [1]. Similar appear between energy levels dot. conclusions allow future where electronic properties scattering rate being controlled parameter. single particle picture, chaotic or disordered crudely as arising from window size 2ND, matrix elements these leads. Here D mean spacing state, N (i.e., lead has 2Ne 2 h). assume perfectly coupled Coulomb blockade insignificant. The geometry, including both states, Ne h. [1], range 1 3. weak perpendicular B applied. strong enough break time-reversal symmetry orbital motion, but not produce significant Zeeman splitting. Then, absent 0, satisfy