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arXiv · 2508.07491

A Method for Constructing Quasi-Random Peaked Quantum Circuits

O. G. Udalov
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Abstract

An algorithm is proposed for constructing quasi-random "peaked" quantum circuits, i.e., circuits whose final qubit state exhibits a high probability concentration on a specific computational basis state. These circuits consist of random gates arranged in a brick-wall architecture. While the multiqubit state in the middle of the circuit can exhibit significant entanglement, the final state is, with high probability, a predetermined pure bitstring. A technique is introduced to obscure the final bitstring in the structure of the quantum circuit. The algorithm allows precise control over the probability of the final peaked state. A modified version of the algorithm enables the construction of double- or multi-peaked quantum circuits. The matrix product state (MPS) method is evaluated for simulating such circuits; it performs effectively for shallow peaked circuits but offers no significant advantage for deeper ones.

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O. G. Udalov. 2025-08-10. A Method for Constructing Quasi-Random Peaked Quantum Circuits. https://arxiv.org/abs/2508.07491

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