| Quantum information science is an emerging interdisciplinary tocommunicate and compute base on the principles of quantummechanics. Its development improve the information security andtechnological competitiveness of the country, and on the other hand,the study on the quantum information science will enhance theunderstand to the quantum mechanics itself. Quantum informationprocessing have show enormous potential in the quantumcryptography, large numbers factorization, large database searches,and the quantum simulation when compared to the classicalinformation processing, essentially rely on coherent superpositionand entanglement of quantum systems. However, the inevitableinteraction between quantum system and surrounding environmentdestroy the unitary evolution of the quantum system, leads to the lossof quantum coherence. Quantum coherence is the foundation for mostquantum information tasks. These non-unitary evolution which calleddecoherence, is the biggest obstacle to achieve quantum informationprocessing.In order to overcome the difficulties caused by decoherence, theresearchers developed a series of methods to eliminate lecherouseffects, such as quantum error correction codes, quantum avoid error codes. In recent years, an open-loop control method by use of anexternal field to realize the dynamical decoupling between systemand environment have attract great interest, this new quantumcontrol methods can be more proactive and more effective protectionsystem coherence. This paper will study the dynamical decoupling inthe quantum high-dimensional system, the use of the periodicdecoupling sequence take a complete decoupling to the dephasingenvironment. For dissipative environment, we construct aconcatenated pulse sequences and performance better than theperiodic sequence with the same number of pulses under someconditions. For multi-particle entanglement, we designed thedecoupling sequence composed by local operations, can effectivelysuppress entangled decoherence. |
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