Quantum state preparation and nonunitary evolution with diagonal operators

  title={Quantum state preparation and nonunitary evolution with diagonal operators},
  author={Anthony W. Schlimgen and Kade Head-Marsden and LeeAnn M. Sager-Smith and Prineha Narang and David A. Mazziotti},
  journal={Physical Review A},
Realizing non-unitary transformations on unitary-gate based quantum devices is critically important for simulating a variety of physical problems including open quantum systems and subnormalized quantum states. We present a dilation based algorithm to simulate non-unitary operations using probabilistic quantum computing with only one ancilla qubit. We utilize the singular-value decomposition (SVD) to decompose any general quantum operator into a product of two unitary operators and a diagonal… 

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