Kumar Bhaskar, Rajagopal Prabhu
Indian Institute of Technology Madras, Chennai, 600036, India.
Sci Rep. 2024 Oct 6;14(1):23258. doi: 10.1038/s41598-024-73662-8.
Phonon antibunching, a phenomenon arising from the quantum statistics of mechanical vibrations, has attracted significant attention due to its potential applications in quantum information processing, sensing, and energy harvesting. Here, we present a comprehensive investigation of phonon antibunching in a system consisting of three weakly nonlinear coupled nanomechanical resonators. We analytically derive and study the antibunching behavior of phonons in the proposed system and bring insight into the underlying mechanisms. The optimal phonon blockade results from destructive quantum interference due to distinct two-phonon excitation pathways. Due to this quantum interference, these unconventional phonon blockade systems can achieve antibunched statistics even in weakly nonlinear regimes, in contrast to conventional phonon blockade systems that require strong nonlinearity. We show that with the inclusion of an additional resonator, there are multiple additional two-phonon excitation pathways compared to two resonator cases, which results in stronger phonon antibunching and supports single phonon for longer duration. These findings are interesting for practical phononics using coupled-resonator systems.
声子反聚束是一种源于机械振动量子统计的现象，因其在量子信息处理、传感和能量收集方面的潜在应用而备受关注。在此，我们对由三个弱非线性耦合纳米机械谐振器组成的系统中的声子反聚束进行了全面研究。我们通过解析推导并研究了所提出系统中声子的反聚束行为，并深入了解了其潜在机制。最优的声子阻塞源于不同双声子激发路径导致的相消量子干涉。由于这种量子干涉，与需要强非线性的传统声子阻塞系统相比，这些非传统的声子阻塞系统即使在弱非线性区域也能实现反聚束统计。我们表明，与双谐振器情况相比，加入一个额外的谐振器会有多个额外的双声子激发路径，这导致更强的声子反聚束，并能使单声子维持更长时间。这些发现对于使用耦合谐振器系统的实际声子学来说很有意思。
