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arXiv 1705.04872cond-mat.mes-hallquant-ph
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石墨烯量子粘附的辐射修正

Radiative Corrections to Quantum Sticking on Graphene

Sanghita Sengupta, Dennis P. Clougherty

摘要:

我们使用四种不同的方法研究了原子氢对悬浮石墨烯的粘附率,其中包括多声子发射过程的贡献。我们比较了(1)原子自能的环展开,(2)非交叉近似(NCA),(3)独立玻色子模型近似(IBMA)和(4)首阶软声子重算方法(SPR)计算粘滞率的结果.环展开揭示了一个红外问题,类似于QED中臭名昭著的红外问题。2-环对粘附率的贡献给出了对于大膜趋于发散的结果。后三种方法解决了这个红外问题,并给出了在无限膜的极限下有限的结果。我们发现,对于微膜(尺寸范围为100 nm至10 $μ$ m),后三种方法得到的结果是彼此吻合良好,并产生相对于最低阶黄金法则率被轻度抑制的粘附率。最后,我们发现SPR粘附率随着膜尺寸的增加而缓慢下降到零,而NCA和IBMA速率在此极限下趋于非零常数。因此,近似的粘附率可以是敏感的大膜的软声子发射的影响。

英文摘要:

We study the sticking rate of atomic hydrogen to suspended graphene using four different methods that include contributions from processes with multiphonon emission. We compare the numerical results of the sticking rate obtained by: (1) the loop expansion of the atom self-energy, (2) the non-crossing approximation (NCA), (3) the independent boson model approximation (IBMA), and (4) a leading-order soft-phonon resummation method (SPR). The loop expansion reveals an infrared problem, analogous to the infamous infrared problem in QED. The 2-loop contribution to the sticking rate gives a result that tends to diverge for large membranes. The latter three methods remedy this infrared problem and give results that are finite in the limit of an infinite membrane. We find that for micromembranes (sizes ranging 100 nm to 10 $μ$m), the latter three methods give results that are in good agreement with each other and yield sticking rates that are mildly suppressed relative to the lowest-order golden rule rate. Lastly, we find that the SPR sticking rate decreases slowly to zero with increasing membrane size, while both the NCA and IBMA rates tend to a nonzero constant in this limit. Thus, approximations to the sticking rate can be sensitive to the effects of soft-phonon emission for large membranes.

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。

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