  Generating on-demand maximally entangled states is one of the corner stones
for quantum information processing. Parity measurements can serve to create
Bell states and have been implemented via an electronic Mach-Zehnder
interferometer among others. However, the entanglement generation is
necessarily harmed by measurement induced dephasing processes in one of the two
parity subspace. In this work, we propose two different schemes of continuous
feedback for a parity measurement. They enable us to avoid both the
measurement-induced dephasing process and the experimentally unavoidable
dephasing, e.g. due to fluctuations of the gate voltages controlling the
initialization of the qubits. We show that we can generate maximally entangled
steady states in both parity subspaces. Importantly, the measurement scheme we
propose is valid for implementation of parity measurements with feedback loops
in various solid-state environments.
