Bistability and anomalies in absorption and resonance scattering of intense light

Y. Toyozawa

K. M. Leung

Intrinsic optical bistability in the scattering and absorption of light from Rayleigh-particle-sized microparticles having an intensity-dependent refractive index is theoretically investigated. For particles near plasmon resonances optical switching also occurs by sweeping the frequency across the resonance at fixed incident intensity above a certain threshold. Several orders of magnitudes of reduction in the switching intensities are possible near sharp resonances, and an optical transistor mode with a very sizable differential gain can be achieved.

K. M. Leung

Intrinsic optical bistability in the scattering and absorption of light from Rayleigh‐sized microparticles having an intensity‐dependent refractive index is theoretically investigated. For particles near plasmon resonances optical switching occurs with several orders of magnitude reduction in the switching intensity. Besides acting as an optical memory element whose size is small compared with the incident wavelength, the microparticle also exhibits an optical transistor mode with a sizable differential gain.

Pavel A Apanasevich

B. R. Mollow

Mathieu Jeannin, Jean‐Michel Manceau, R. Colombelli

We propose a unified description of intersubband absorption saturation for quantum wells inserted in a resonator, both in the weak and strong light-matter coupling regimes. We demonstrate how absorption saturation can be engineered. In particular, we show that the saturation intensity increases linearly with the doping in the strong coupling regime, while it remains doping independent in weak coupling. Hence, countering intuition, the most suitable region to exploit low saturation intensities is not the ultrastrong coupling regime, but is instead at the onset of the strong light-matter coupling. We further derive explicit conditions for the emergence of bistability. This Letter sets the path toward, as yet, nonexistent ultrafast midinfrared semiconductor saturable absorption mirrors (SESAMs) and bistable systems. As an example, we show how to design a midinfrared SESAM with a 3 orders of magnitude reduction in saturation intensity, down to ≈5 kW cm^{-2}.