We demonstrate an inherently self-stable Brillouin fiber laser in telecom wavelengths, stemming from a natural thermal
feedback mechanism. Such lasers demonstrate great stability which significantly overcomes the hampering drift often
associated with fiber lasers.
Coherent Perfect Absorbers (CPAs) are optical cavities which can be described as time-reversed lasers where light waves that enter the cavity, coherently interfere and react with the intra-cavity losses to yield perfect absorption. In contrast to lasers, which benefit from high coherency and narrow spectral linewidths, for absorbers these properties are often undesirable as absorption at a single frequency is highly susceptible to spectral noise and inappropriate for most practical applications. Recently, a new class of cavities, characterized by a spectrally wide resonance has been proposed. Such resonators, often referred to as White Light Cavities (WLCs), include an intra-cavity superluminal phase element, designed to provide a phase response with a slope that is opposite in sign and equal in magnitude to that of light propagation through the empty cavity. Consequently, the resonance phase condition in WLCs is satisfied over a band of frequencies providing a spectrally wide resonance. WLCs have drawn much attention due to their attractiveness for various applications such as ultra-sensitive sensors and optical buffering components. Nevertheless, WLCs exhibit inherent losses that are often undesirable. Here we introduce a simple wideband CPA device that is based on the WLC concept along with a complete analytical analysis. We present analytical and FDTD simulations of a practical, highly compact (12µm), Silicon based WLC-CPA that exhibits a flat and wide absorption profile (40nm) and demonstrate its usefulness as an optical pulse terminator (>35db isolation) and an all optical modulator that span the entire C-Band and exhibit high immunity to spectral noise.
We present a comprehensive study of the properties of a superluminal fiber laser based super-sensor employing Brillouin
gain. Exact analytical expression for the required parameters and the sensitivity enhancement are derived. The
dependence of the sensitivity enhancement on the measured phase shift is found to be highly nonlinear, rapidly
increasing at smaller quanta. The minimal detectable shift due to shot noise is found to be smaller by 8 orders of
magnitudes compared to conventional laser sensors. The tradeoffs between the attainable sensitivity enhancement, the
cavity dimensions and the impact of the cavity roundtrip loss are studied in details providing a set of design rules for the
optimization of the super-sensor.
We present and theoretically study a superluminal fiber laser based super-sensor utilizing Brillouin
gain. The white light cavity condition is attained by introducing a phase shift component
comprising an additional cavity into the main cavity. By properly controlling the parameters of the
laser cavity and those of the phase component it is possible to attain sensitivity enhancement of
many orders of magnitude compared to that of conventional laser sensors. The tradeoffs between
the attainable sensitivity enhancement, the cavity dimensions and cavity roundtrip loss are studied
in details, providing a set of design rules for the optimization of the super-sensor.