arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0902.2243cond-mat.mes-hallcond-mat.str-el
收藏

Aharonov-Bohm干涉仪中电子通过量子点链输运的退耦和反共振

Decoupling and antiresonance in electronic transport through a quantum dot chain embodied in an Aharonov-Bohm interferometer

Yu Han, Weijiang Gong, Haina Wu, Guozhu Wei

摘要:

对Aharonov-Bohm干涉仪中量子点链的电子输运进行了理论研究。在这样的系统中,我们发现只有当量子点数目相同时,量子点链中的某些分子态才能从量子点的引出端退耦。也就是说,在没有磁通量的情况下,所有奇数分子状态与引线解耦,但是当引入适当的磁通量时,所有偶数分子状态与引线解耦。有趣的是,反共振的位置在电子输运光谱是独立的去耦的分子状态的变化。此外,当在二阶近似下考虑多体效应时,我们发现退耦的出现引起了电子-空穴对称性的明显破坏。通过调节通过任一子环的磁通量,一些分子态从一个引线解耦,但仍然耦合到另一个,然后发生一些新的反共振。

英文摘要:

Electronic transport through a quantum dot chain embodied in an Aharonov-Bohm interferometer is theoretically investigated. In such a system, it is found that only for the configurations with the same-numbered quantum dots side-coupled to the quantum dots in the arms of the interferometer, some molecular states of the quantum dot chain decouple from the leads. Namely, in the absence of magnetic flux all odd molecular states decouple from the leads, but all even molecular states decouple from the leads when an appropriate magnetic flux is introduced. Interestingly, the antiresonance position in the electron transport spectrum is independent of the change of the decoupled molecular states. In addition, when considering the many-body effect within the second-order approximation, we show that the emergence of decoupling gives rise to the apparent destruction of electron-hole symmetry. By adjusting the magnetic flux through either subring, some molecular states decouple from one lead but still couple to the other, and then some new antiresonances occur.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑