Our study on tunable anti-lasing or commonly known as coherent perfect absorption can be expressed with a simple formula as for TE-polarization. The expression can be used to estimate all necessary parameters required for anti-lasing, such as, materials type, it's thickness, angle of incidences and wavelength of the light.
Recently, it has been observed that a tremendous interest is found in the anomaly of anti-lasing, particularly in micro or nano-structures, where the incident lights shining from the opposite side of anti-lasing materials are 100% absorbed. The positive imaginary part of a complex permittivity is the essential requirement for absorbing media, which is involved in the occurrence of anti-lasing. Apart from these the dependence of anti-lasing varies with 1: the concentration or density of the medium 2: the wavelength of shining lights, and 3: the angle of incidence of the lights. This theoretical expression can describe all the parameters of anti-lasing. This presentation contains how one can derive the expression from EM waves for oblique incidences with the help of Maxwell's and EM boundary conditions. We will see several examples of anti-lasing with the help of the expression.
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What will audience learn from your presentation?
- The logical step-by-step argument for the development of the theoretical formula of anti-lasing.
- Comparison of some real-time examples of anti-lasing with the expression.
- The usefulness of the formula to achieve anti-lasing.
- Improvement of accuracy in our anti-lasing experiments.
- The future aspect of the formula