  We investigated the electron transport property of the InGaAs/GaAs double
quantum dots, the electron g-factors of which are different from each other. We
found that in a magnetic field, the resonant tunneling is suppressed even if
one of the Zeeman sublevels is aligned. This is because the other misaligned
Zeeman sublevels limit the total current. A finite broadening of the misaligned
sublevel partially relieves this bottleneck effect, and the maximum current is
reached when interdot detuning is half the Zeeman energy difference.
