Transforming pure and mixed states using an NMR quantum homogenizer

The universal quantum homogenizer can transform a qubit from any state to any other state with arbitrary accuracy, using only unitary transformations to perform this task. Here we present an implementation of a finite quantum homogenizer using nuclear magnetic resonance (NMR), with a four-qubit system. We compare the homogenization of a mixed state to a pure state and the reverse process. After accounting for the effects of decoherence in the system, we find the experimental results to be consistent with the theoretical symmetry in how the qubit states evolve in the two cases. We analyze the implications of this symmetry by interpreting the homogenizer as a physical implementation of pure state preparation and information scrambling.

Automated summary

An implementation of a finite quantum homogenizer using nuclear magnetic resonance (NMR) with a four-qubit system is presented. Experimental results are consistent with the theoretical symmetry in qubit state evolution, revealing the physical significance of the homogenizer for pure state preparation and information scrambling.