Iles-Smith Jake, Nazir Ahsan, McCutcheon Dara P S
Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH, UK.
School of Physics and Astronomy, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
Nat Commun. 2019 Jul 10;10(1):3034. doi: 10.1038/s41467-019-10909-3.
Vibrational environments are commonly considered to be detrimental to the optical emission properties of solid-state and molecular systems, limiting their performance within quantum information protocols. Given that such environments arise naturally it is important to ask whether they can instead be turned to our advantage. Here we show that vibrational interactions can be harnessed within resonance fluorescence to generate optical states with a higher degree of quadrature squeezing than in isolated atomic systems. Considering the example of a driven quantum dot coupled to phonons, we demonstrate that it is feasible to surpass the maximum level of squeezing theoretically obtainable in an isolated atomic system and indeed come close to saturating the fundamental upper bound on squeezing from a two-level emitter. We analyse the performance of these vibrationally-enhanced squeezed states in a phase estimation protocol, finding that for the same photon flux, they can outperform the single mode squeezed vacuum state.
振动环境通常被认为会损害固态和分子系统的光发射特性，限制它们在量子信息协议中的性能。鉴于这种环境是自然产生的，重要的是要问它们是否反而能为我们所用。在这里，我们表明振动相互作用可以在共振荧光中得到利用，以产生比孤立原子系统具有更高正交压缩程度的光学态。以与声子耦合的驱动量子点为例，我们证明超越孤立原子系统理论上可获得的最大压缩水平并确实接近达到两能级发射体压缩的基本上限是可行的。我们在相位估计协议中分析了这些振动增强压缩态的性能，发现对于相同的光子通量，它们可以优于单模压缩真空态。
