  Quantum states are usually fragile which makes quantum computation being not
as stable as classical computation. Quantum correction codes can protect
quantum states but need a large number of physical qubits to code a single
logic qubit. Alternatively, the protection at the hardware level has been
recently developed to maintain the coherence of the quantum information by
using symmetries. However, it generally has to pay the expense of increasing
the complexity of the quantum devices. In this work, we show that the
protection at the hardware level can be approached without increasing the
complexity of the devices. The interplay between the spin-orbit coupling and
the Zeeman splitting in the semiconductor allows us to tune the Josephson
coupling in terms of the spin degree of freedom of Cooper pairs, the hallmark
of the superconducting spintronics. This leads to the implementation of the
parity-protected 0-$\pi$ superconducting qubit with only one highly transparent
superconductor-semiconductor Josephson junction, which makes our proposal
immune from the various fabrication imperfections.
