Abstract
<title>Abstract</title> <p>For quantum communication and computation protocols, preparing W states is a fundamental requirement. Traditionally, deterministic W-state generation requires non-Clifford rotations. In fault-tolerant architectures, the cost of Tgate synthesis and Magic State Distillation (MSD)[1] is very high. As a result, non-Clifford rotations for W state preparation introduce significant overhead. This research paper proposes a heralded, probabilistic circuit for the 3-qubit W-state[2] preparation using only Clifford gates[1] and one ancillary qubit. The quantum circuit utilizes the interaction between two Bell pairs[3], followed by post-selection, and achieves a success probability of 0.75. The proposed protocol maintains a T-count of zero. It also reduces the circuit depth and error susceptibility compared to standard unitary methods. This paper provides details of the protocol and compares its gate-count efficiency with that of existing methods. The proposed protocol substitutes high-overhead non-Clifford gates for a manageable post-selection loss and thus, provides a resource-efficient and robust alternative for W-state preparation in near-term hardware and early fault-tolerant systems.</p>