Temperature Effect on Mølmer and Sørensen Model: A Two-Time Green's Function Method
Wei Li, Hongmin Zhao, Jia-tih Lin · International Journal of Quantum Information · 2003
Using two-time Green's function we analyze the effect of temperature on the Mølmer and Sørensen (M–S) model of cold trapped ion quantum computer. A formula for the deviation of an internal state from its ground state is derived in the first-order approximation. The fluctuation of internal state caused by thermal motion is also discussed. The deviation of internal state when different trap parameters changes with the temperature are given too. The upper temperature limit for regular quantum computation is obtained and our result is in agreement with experiment.