Quantum Transport in DNA Heterostructures: Implications for Nanoelectronics
Quantum Transport in DNA Heterostructures: Implications for Nanoelectronics
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DOI：
10.1021/acsanm.1c01087
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发表时间：
2021-09
影响因子：
5.9
通讯作者：
S. Patil;Hashem M. Mohammad;Vivek Chawda;Niraj Sinha;R. K. Singh;J. Qi;M. Anantram
中科院分区：
文献类型：
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作者：
S. Patil;Hashem M. Mohammad;Vivek Chawda;Niraj Sinha;R. K. Singh;J. Qi;M. Anantram
了解基于 DNA 异质结构的量子传输是推进 DNA 纳米电子学领域的关键，其中量子干涉将发挥重要作用。可以分别使用腺嘌呤-胸腺嘧啶（AT）和鸟嘌呤-胞嘧啶（GC）碱基对在DNA中构建电子“屏障”和“孔”，因为它们的电离势显着不同。我们研究了势垒和阱的宽度对空穴传输的影响。对能量最小化的 DNA 结构进行密度泛函理论计算，然后进行包括退相干在内的量子输运计算。通过构建哈密顿量模型并选择性地关闭长程和链间相互作用来探测器件物理。该研究的主要成果包括：（1）DNA异质结构与固态半导体异质结构的互补；也就是说，电导率分别随着势垒和阱宽度的增加而急剧下降； (2) DNA 异质结构中的量子干涉是稳健的，从传输共振中的清晰峰值可以看出，即使存在退相干； (3) DNA构象对于决定等效异质结构的电导具有深远的作用； (4)结构差异导致更接近的HOMO能级和更多的离域态。因此，即使 π-π 轨道重叠较弱，某些链中的传输也可以高效。
Understanding quantum transport through DNA-based heterostructures is a key to advancing the field of DNA nanoelectronics, where quantum interference would play a significant role. Electronic “barriers” and “wells” can be constructed in DNA using adenine–thymine (AT) and guanine–cytosine (GC) base pairs, respectively, as their ionization potentials differ significantly. We investigate the influence of the width of barriers and wells on hole transport. Density functional theory calculations are performed on energy-minimized DNA structures, followed by quantum transport calculations including decoherence. The device physics is probed by constructing a model Hamiltonian and selectively turning off long-range and interstrand interactions. Major outcomes of the study include the following: (1) DNA heterostructures complement the solid-state semiconductor counterparts; that is, conductance decreases sharply and marginally with an increase in barrier and well width, respectively; (2) quantum interference in DNA heterostructures is robust, as seen by clear peaks in the transmission resonance even with decoherence; (3) DNA conformation has a profound role in deciding the conductance of equivalent heterostructures; and (4) structural differences lead to closer HOMO energy levels and more delocalized states. As a result, transport can be efficient in some strands even with weaker π–π orbital overlap.