Spin Qubit Decoherence and Entanglement Induced by 1D Quantum Spin Baths

自旋量子位元與一維自旋環境交互作用之消相干與糾纏態研究

洪若慈(Jo-Tzu Hung)

指導教授 ： 陳柏中

國立清華大學/理學院/物理學系/碩士(2008年)

摘要

Spin decoherence induced by spin baths has become an important subject in the field of quantum information science and quantum computing. In this work, the Heisenberg XXZ spin chain, which has a rich phase diagram, functions as a spin bath. I investigate spin-1/2 qubit decoherence as well as entanglement by mean of time-dependent density matrix renormalization group (t-DMRG). I find that induced decoherence and entanglement crucially depends on the phase
of the spin bath. Moreover, for various interaction types and coupling strengths between the qubit(s) and the spin bath, the induced decoherence and entanglement differs. These show that there is a competition between the induced decoherence and entanglement. Finally, I stimulate two-qubit (dis)entanglement dynamics via a common bath and entanglement sudden death is also observed.

關鍵字

密度矩陣重整化群 ； 量子資訊 ； HASH(0x1c4e8370)

並列摘要

無資料

並列關鍵字

Density matrix renormalization group ； DMRG ； Quantum information

參考文獻

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