Cubic dresselhaus spin-orbit coupling in 2D electron quantum dots

We study effects of the oft-neglected cubic Dresselhaus spin-orbit coupling (i.e., proportional to p(3)) in GaAs/AlGaAs quantum dots. Using a semiclassical billiard model, we estimate the magnitude of the spin-orbit induced avoided crossings in a closed quantum dot in a Zeeman field. Using previous analyses based on random matrix theory, we calculate corresponding effects on the conductance through an open quantum dot. Combining our results with an experiment on an 8 mu m(2) quantum dot [D. M. Zumbuhl , Phys. Rev. B 72, 081305 (2005)] suggests that (1) the GaAs Dresselhaus coupling constant gamma is approximately 9 eV A(3), significantly less than the commonly cited value of 27.5 eV A(3), and (2) the majority of the spin-flip effects can come from the cubic Dresselhaus term.