Coherent nonlinear transfer from matter to light by using anharmonic semiconductor dipoles

Nonlinear optics has emerged as a fundamental material property required in quantum technologies. However, the lack of nonlinear effects observed in the few-photon regime with typical optical materials makes it necessary to search for other types of systems. We propose a cavity quantum electrodynamics (QED) approach to transfer coherent material anharmonicity to a photonic mode in the THz regime, which generates stationary power-dependent nonlinear shifts. The light-matter system considers a semiconductor structure composed of two intersubband quantum wells (QW) coupled to the near field of a nanoantenna. Semiconductor dipoles are selected for their versatile fabrication capabilities, allowing for tuning the anharmonicity in comparison with molecular systems [1]. We analytically derive the nonlinear phase shifts, which agree with fully quantum numerical calculations, by solving the Lindblad master equation. We obtain phase shifts of the order of 0.1π by implementing femtosecond pulses with power intensities of a few microwatts [2]. Our results demonstrate that phase control can also be performed in the weak-coupling regime, in contrast to conventional cavity QED schemes that require strong light-matter interactions. Our work paves the way for achieving nonlinear phase shifts in the laboratory using the current nanophotonic technology.

[1] J. F. Triana, M. Arias, et.al, J. Chem. Phys., 156, 124110 (2022)

[2] M. Arias, J. F. Triana, A. Delgado, F. Herrera, arXiv.2309.12216