Quantum replication at the Heisenberg limit

TL;DR

This paper demonstrates that probabilistic super-replication of quantum states can produce nearly perfect copies at a quadratic rate, reaching the fundamental Heisenberg limit of quantum information proliferation.

Contribution

It introduces a probabilistic super-replication process that achieves the quadratic replication rate dictated by quantum mechanics and links it to the Heisenberg limit in quantum metrology.

Findings

Replication error vanishes rapidly when M is small compared to N^2

Quadratic replication rate is the ultimate limit set by quantum mechanics

Process achieves nearly perfect quantum state copies at the Heisenberg limit

Abstract

No process in nature can perfectly clone an arbitrary quantum state. But is it possible to engineer processes that replicate quantum information with vanishingly small error? Here we demonstrate the possibility of probabilistic super-replication phenomena where N equally prepared quantum clocks are transformed into a much larger number of M nearly perfect replicas, with an error that rapidly vanishes whenever M is small compared to the square of N. The quadratic replication rate is the ultimate limit imposed by Quantum Mechanics to the proliferation of information and is fundamentally linked with the Heisenberg limit of quantum metrology.