  The choice of substrate orientation for semiconductor quantum dot circuits
offers opportunities for tailoring spintronic properties such as g-factors for
specific functionality. In this letter, we demonstrate the operation of a
few-electron double quantum dot circuit fabricated from a (110)-oriented GaAs
quantum well. We estimate the in-plane electron g-factor from the profile of
the enhanced inter-dot tunneling (leakage) current near zero magnetic field.
Spin-blockade due to Pauli exclusion can block inter-dot tunneling. However,
this blockade becomes inactive due to hyperfine interaction mediated spin
flip-flop processes between electron spin states and the nuclear spin of the
host material. The g-factor of absolute value ~0.1 found for a magnetic field
parallel to the direction [11(bar)0], is approximately a factor of four lower
than that for comparable circuits fabricated from material grown on
widely-employed standard (001) GaAs substrates, and is in line with reported
values determined by purely optical means for quantum well structures grown on
(110) GaAs substrates.
