Higher Order Decompositions of Ordered Operator Exponentials

  title={Higher Order Decompositions of Ordered Operator Exponentials},
  author={Nathan Wiebe and Dominic W. Berry and Peter H{\o}yer and Barry C. Sanders},
  journal={arXiv: Mathematical Physics},
We present a decomposition scheme based on Lie-Trotter-Suzuki product formulae to represent an ordered operator exponential as a product of ordinary operator exponentials. We provide a rigorous proof that does not use a time-displacement superoperator, and can be applied to non-analytic functions. Our proof provides explicit bounds on the error and includes cases where the functions are not infinitely differentiable. We show that Lie-Trotter-Suzuki product formulae can still be used for… 

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