Quantum metrology in a driven-dissipation down-conversion system beyond the parametric approximation
arxiv(2024)
摘要
We investigate quantum metrology in a degenerate down-conversion system
composed of a pump mode and two degenerate signal modes. In the conventional
parametric approximation, the pump mode is assumed to be constant, not a
quantum operator. We obtain the measurement precision of the coupling strength
between the pump mode and two degenerate signal modes beyond the parametric
approximation. Without a dissipation, the super-Heisenberg limit can be
obtained when the initial state is the direct product of classical state and
quantum state. This does not require the use of entanglement resources which
are not easy to prepare. When the pump mode suffers from a single-photon
dissipation, the measurement uncertainty of the coupling strength is close to 0
as the coupling strength approaches 0 with a coherent driving. The direct
photon detection is proved to be the optimal measurement. This result has not
been changed when the signal modes suffer from the two-photon dissipation. When
the signal modes also suffer from the single-mode dissipation, the information
of the coupling strength can still be obtained in the steady state. In
addition, the measurement uncertainty of the coupling strength can also be
close to 0 and become independent of noise temperature as the critical point
between the normal and superradiance phase approaches. Finally, we show that a
driven-dissipation down-conversion system can be used as a precise quantum
sensor to measure the driving strength.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要