Pure and Efficient Single-Photon Sources by Shortening and Functionalizing Air-Suspended Carbon Nanotubes
Pure and Efficient Single-Photon Sources by Shortening and Functionalizing Air-Suspended Carbon Nanotubes
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DOI：
10.1021/acsanm.9b02209
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发表时间：
2020-01-01
影响因子：
5.9
通讯作者：
Maki, Hideyuki
中科院分区：
文献类型：
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作者：
Kawabe, Rintaro;Takaki, Hiroshi;Maki, Hideyuki
基于单壁碳纳米管（SWCNT）的单光子源（SPS）可以在室温和通信波长下在硅芯片上产生单光子，是非制冷片上量子信息光电子学的一个很有前途的候选者。然而，对于量子信息的应用，如量子计算和量子密码学，更高性能的SPS，表现出高纯度和高效率的单光子产生的要求。在这里，我们从理论上提出了高性能的SPS，同时实现高纯度和高效率的单光子产生，通过使用短和功能化的空气悬浮单壁碳纳米管。模拟激子动力学，时间分辨光致发光和光子相关性质表明，激子-激子湮灭，末端淬灭，并在缺陷引入的功能化，如氧或芳基掺杂捕获发挥重要作用，在确定的发射和单光子性能，这强烈依赖于单壁碳纳米管的长度和激发强度。我们发现，高性能的SPS，同时表现出99.87%的高单光子纯度和99.84%的高单光子产生效率，可以实现通过使用空气悬浮的功能化单壁碳纳米管的长度约为100 nm的高激发条件下。这种理想的SPS可以在室温下实现高速率和长距离的量子密钥分发。
A single-photon source (SPS) based on a single-walled carbon nanotube (SWCNT) is a promising candidate for uncooled on-chip quantum information optoelectronics because a single photon can be generated at both room temperature and telecommunication wavelengths on silicon chips. However, for the applications of quantum information, such as quantum computing and quantum cryptography, higher performance SPSs that exhibit both high purity and high efficiency of single-photon generation are required. Here, we theoretically propose high-performance SPSs that simultaneously achieve high-purity and high-efficiency single-photon generation by using short and functionalized air-suspended SWCNTs. The simulated exciton dynamics, time-resolved photoluminescence, and photon correlation properties indicate that exciton-exciton annihilation, end quenching, and trapping in the defect introduced by functionalization such as oxygen or aryl doping play important roles in determining the emission and single-photon properties, which strongly depend on SWCNT length and excitation intensity. We found that high performance SPSs that exhibit simultaneously high single-photon purity of 99.87% and high single-photon generation efficiency of 99.84% can be realized by using air-suspended functionalized SWCNTs with a length of approximately 100 nm under high excitation conditions. This ideal SPS can enable high rate and long-distance quantum key distributions at room temperature.