English

Coherence Fraction

Quantum Physics 2019-06-21 v1

Abstract

The concept of entanglement fraction is generalized to define coherence fraction of a quantum state. Precisely, it quantifies the proximity of a quantum state to maximally coherent state and it can be used as a measure of coherence. Coherence fraction has a connection with l1l_1-norm coherence and provides the criteria of coherence distillability. Optimal coherence fraction corresponding to a channel, defined from this new idea of coherence fraction, obeys a complementary relation with its decohering power. The connection between coherence fraction and l1l_1-norm coherence turns to hold for bipartite pure states and XX states too. The bipartite generalization shows that the local coherence fractions of a quantum state are not free and they are bounded by linear function of its global coherence fraction. Dynamics of optimal coherence fraction is also studied for single sided and both sided application of channels. Numerical results are provided in exploring properties of optimal coherence fraction.

Keywords

Cite

@article{arxiv.1906.08326,
  title  = {Coherence Fraction},
  author = {Sumana Karmakar and Ajoy Sen and Indrani Chattopadhyay and Amit Bhar and Debasis Sarkar},
  journal= {arXiv preprint arXiv:1906.08326},
  year   = {2019}
}

Comments

12 pages, 4 figures, latex2e, comments welcome, submitted to qip

R2 v1 2026-06-23T09:58:27.177Z