We propose a scalable and deterministic protocol for growing large multiqubit states starting from two-qubit nonmaximally entangled pure states, where the bipartite entanglement in the resultant state is higher than the maximum of the available entangled qubit pairs. This is achieved via a truncation of the Hilbert space corresponding to a subsystem of qubits to a space that hosts a single qubit, brought about by a multiqubit measurement assisted by the graph basis. We prove its equivalence to a repetitive two-qubit measurement-based protocol, and demonstrate realization of the required two-qubit measurement via a two-qubit parity measurement, thereby establishing the implementability of the protocol. We derive lower and upper bounds of the bipartite entanglement concentrated after a given number of rounds of measurements, where the entanglement of the available qubit pairs are notnecessarily equal. We further discuss the effect of possible imperfections that may arise in the protocol and its robustness towards such imperfections. We demonstrate the usefulness of our proposal by applying it to create generalized Greenberger-Horne-Zeilinger states on arbitrary number of qubits, thereby underlining the possibility of creating maximally entangled qubit pairs via qubit-local projection measurements.

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• Entanglement manipulation
• Entanglement production
• Quantum entanglement