Tunable virtual gain in resonantly absorbing media

Abstract

Virtual gain refers to the simulation of real light amplification using radiation with exponentially decaying amplitude, so that its complex frequency corresponds to the scattering pole. We theoretically study virtual gain in a two-level resonant medium for different regimes of light-matter interaction depending on the radiation intensity. We show that virtual gain at the pole can be most clearly observed for low intensities, when the medium is absorbing, in contrast to the saturated medium at high intensities. The efficiency of virtual gain can be tuned with the light intensity and can be controlled dynamically through the population inversion of the medium. Our results show that resonantly absorbing media paradoxically mimics gain-like response, which admit a number of related phenomena and methods to mold both optical signals and material properties without relying on instability-prone gain media.

11 pages, 9 figures; to appear in Phys. Rev. A

References in corpus (10)

• Coherent Perfect Absorbers: Time-reversed Lasers
• Dynamics of light propagation in spatiotemporal dielectric structures
• $\hslash \omega$ versus $\hslash \mathbf{k}$: Dispersion and Energy Constraints on Time-Varying Photonic Materials and Time Crystals
• Beyond Bounds on Light Scattering with Complex Frequency Excitations
• Propagation of subcycle pulses in a two-level medium: Area-theorem breakdown and pulse shape
• Compression of an intensive light pulse in a dense resonant medium and photonic-band-gap structures containing it
• Controlled absorption and all-optical diode action due to collisions of self-induced transparency solitons
• Lighting of a monochromatic scatterer with virtual gain
• Disordered resonant media: Self-induced transparency versus light localization
• Optical kinks and kink-kink and kink-pulse interactions in resonant two-level media