Villas-Boas Celso J, Rossatto Daniel Z
Departamento de Física, Universidade Federal de São Carlos, 13565-905 São Carlos, São Paulo, Brazil.
Universidade Estadual Paulista (Unesp), Campus Experimental de Itapeva, 18409-010 Itapeva, São Paulo, Brazil.
Phys Rev Lett. 2019 Mar 29;122(12):123604. doi: 10.1103/PhysRevLett.122.123604.
The multiphoton Jaynes-Cummings model is investigated and applications in quantum information science are explored. Considering the strong atom-field coupling regime and an N-photon interaction, a nonlinear driving field can perform an arbitrary rotation in the Fock space of a bosonic mode involving the vacuum and an M-Fock state, with M<N. In addition, driving a bosonic mode with a linear coherent field (superposition of many Fock states), only the cavity states within the Fock subspace {|0⟩,|1⟩,…,|N-1⟩} can be populated; i.e., we show how to implement a Fock state filter, or quantum scissor, that restricts the dynamics of a given bosonic mode to a limited Hilbert space. Such a device can be employed as a generator of finite-dimensional quantum-optical states and also as a quantum-optical intensity limiter, allowing as a special case the generation of single-photon pulses. On the other hand, our system also provides a very rich physics in the weak atom-field coupling regime, in particular, multiphoton electromagnetically induced transparencylike phenomena, inducing a narrow (controllable) reflectivity window for nonlinear probe fields. These results are useful for applications in quantum information processing and also motivate further investigations, e.g., the use of an N-photon Jaynes-Cummings system as a qudit with harmonic spectrum and the exploration of multiphoton quantum interference.
研究了多光子Jaynes-Cummings模型,并探索了其在量子信息科学中的应用。考虑强原子-场耦合机制和N光子相互作用,非线性驱动场可以在包含真空和M福克态(M < N)的玻色子模的福克空间中执行任意旋转。此外,用线性相干场(许多福克态的叠加)驱动玻色子模时,只有福克子空间{|0⟩,|1⟩,…,|N - 1⟩}内的腔态可以被占据;也就是说,我们展示了如何实现一个福克态滤波器或量子剪刀,它将给定玻色子模的动力学限制在有限的希尔伯特空间内。这样的器件可以用作有限维量子光学态的发生器,也可以用作量子光学强度限制器,在特殊情况下允许产生单光子脉冲。另一方面,我们的系统在弱原子-场耦合机制下也提供了非常丰富的物理现象,特别是多光子类电磁诱导透明现象,为非线性探测场诱导出一个窄的(可控的)反射率窗口。这些结果对于量子信息处理中的应用很有用,也激发了进一步的研究,例如,将N光子Jaynes-Cummings系统用作具有谐波谱的量子比特以及探索多光子量子干涉。