  Carbon-doped high mobility two-dimensional hole gases grown on (110) oriented
GaAs substrates have been grown with hole mobilities exceeding 10^6 cm^2/Vs in
single heterojunction GaAs/AlGaAs structures. At these high mobilities, a
pronounced mobility anisotropy has been observed. Rashba induced spin-splitting
in these asymmetric structures has been found to be independent on the
transport direction.
