  Quantum coherence of superposed states, especially of entangled states, is
indispensable for many quantum technologies. However, it is vulnerable to
environmental noises, posing a fundamental challenge in solid-state systems
including spin qubits. Here we show a scheme of entanglement engineering where
pure dephasing assists the generation of quantum entanglement at distant sites
in a chain of electron spins confined in semiconductor quantum dots. One party
of an entangled spin pair, prepared at a single site, is transferred to the
next site and then adiabatically swapped with a third spin using a transition
across a multi-level avoided crossing. This process is accelerated by the
noise-induced dephasing through a variant of the quantum Zeno effect, without
sacrificing the coherence of the entangled state. Our finding brings insight
into the spin dynamics in open quantum systems coupled to noisy environments,
opening an avenue to quantum state manipulation utilizing decoherence effects.
