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arXiv · 2011.13937

Mana in Haar-random states

Christopher David White·Justin H. Wilson
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Abstract

Mana is a measure of the amount of non-Clifford resources required to create a state; the mana of a mixed state on $\ell$ qudits bounded by $\le \frac 1 2 (\ell \ln d - S_2)$; $S_2$ the state's second Renyi entropy. We compute the mana of Haar-random pure and mixed states and find that the mana is nearly logarithmic in Hilbert space dimension: that is, extensive in number of qudits and logarithmic in qudit dimension. In particular, the average mana of states with less-than-maximal entropy falls short of that maximum by $\ln \pi/2$. We then connect this result to recent work on near-Clifford approximate $t$-designs; in doing so we point out that mana is a useful measure of non-Clifford resources precisely because it is not differentiable.

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Christopher David White, Justin H. Wilson. 2020-11-27. Mana in Haar-random states. https://arxiv.org/abs/2011.13937

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