To conquer Ohmic losses from metal and enhance pump absorption efficiency of a nanolaser based on surface plasmon
polariton, we theoretically calculate the first magnetic and electric scattering coefficient of a dielectric sphere under a
plane wave excitation with a dielectric constant of around 12. From this calculation, we could retrieve both negative
effective permittivity and permeability of the sphere simultaneously at frequencies around 153 THz in the aids of
Lewin’s theory and the power distribution clearly demonstrate the expected negative Goos-Hänchen effect, which
usually occurred in a negative refractive waveguide, thus creating two energy vortices to trap incident energy and then
promoting the pump absorption efficiency. Meanwhile, a magnetic lasing mode at 167.3 THz is demonstrated and reveals
a magnetic dipole resonance mode and a circulating energy flow within the dielectric sphere, providing a possible
stopped light feedback mechanism to enable the all-dielectric nanolaser. More importantly, the corresponding mode
volume is reduced to 0.01λ3 and a gain threshold of 5.1×103 is obtained. To validate our design of all-dielectric nanolaser,
we employ finite-difference-time-domain simulation software to examine the behavior of the nanolaser. From simulation,
we could obtain a pinned-down population inversion of 0.001 and a lasing peak at around 166.5 THz, which is very
consistent with the prediction of Mie theory. Finally, according to Mie theory, we can regard the all-dielectric nanolaser
as the excitation of material polariton and thus could make an analogue between lasing modes of the dielectric and
metallic nanoparticles.
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