Boixo Sergio, Flammia Steven T, Caves Carlton M, Geremia J M
Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131, USA.
Phys Rev Lett. 2007 Mar 2;98(9):090401. doi: 10.1103/PhysRevLett.98.090401. Epub 2007 Feb 28.
We develop generalized bounds for quantum single-parameter estimation problems for which the coupling to the parameter is described by intrinsic multisystem interactions. For a Hamiltonian with k-system parameter-sensitive terms, the quantum limit scales as 1/Nk, where N is the number of systems. These quantum limits remain valid when the Hamiltonian is augmented by any parameter-independent interaction among the systems and when adaptive measurements via parameter-independent coupling to ancillas are allowed.
我们针对量子单参数估计问题开发了广义界限，其中与参数的耦合由内在多系统相互作用描述。对于具有k系统参数敏感项的哈密顿量，量子极限按1/Nk缩放，其中N是系统的数量。当哈密顿量通过系统之间的任何与参数无关的相互作用增强时，以及当允许通过与辅助系统的与参数无关的耦合进行自适应测量时，这些量子极限仍然有效。
