Experimentally Determining Bloch Parameters of Hamiltonian for Single-Qubit Systems |
| |
| Authors: | ZHANG Ming ZHOU Wei-Wei DAI Hong-Yi LIN Min SUN Zhi-Qiang GONG Er-Ling |
| |
| Affiliation: | 1.College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073, China;2.College of Science, National University of Defense Technology, Changsha 410073, China |
| |
| Abstract: | By considering the identification problem of unknown but fixed Hamiltonian H=S0σ0+ ∑i=x,y,zSiσi where σi (i=x,y,z) are pauli matrices and σ0=I, weexplore the feasibility and limitation of empirically determining the Hamiltonian parameters for quantum systems under experimental conditions imposed by projective measurements and initialization procedures. It may be unsurprising to physicists that one can not obtain the knowledge of S0 no matter what kind of projective measurements and initialization are permitted, but the observation draws our attention to the importance of the parameter identifiability under different experimental condition. It has also been revealed that one can obtain the knowledge of |Sz| and Sx2+Sy2 at most when only the projective measurement |0><0|,| 1><1| is permitted to perform on and initialize the qubit. Further more, we demonstrated that it is feasible to distinguish |Sx|, |Sy|, and |Sz| even without any a priori information about Hamiltonian if at least two kinds of projective measurement or initialization procedures are permitted. It should be emphasized that both projective measurements and initialization procedures play an important role in quantum system identification. |
| |
| Keywords: | Hamiltonian tomography experimental design parameter estimation |
| 本文献已被 维普 等数据库收录！ |
| 点击此处可从《理论物理通讯》浏览原始摘要信息 |
|
点击此处可从《理论物理通讯》下载全文 |
|
