# Power of One Bit of Quantum Information

@article{Knill1998PowerOO, title={Power of One Bit of Quantum Information}, author={Emanuel Knill and Raymond Laflamme}, journal={Physical Review Letters}, year={1998}, volume={81}, pages={5672-5675} }

In standard quantum computation, the initial state is pure and the answer is determined by making a measurement of some of the bits in the computational basis. What can be accomplished if the initial state is a highly mixed state and the answer is determined by measuring the expectation of {sigma}{sub z} on the first bit with bounded sensitivity? This is the situation in high temperature ensemble quantum computation. We show that in this model it is possible to perform interesting physics…

## 371 Citations

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