Design and analysis of a gallium lanthanum sulfide based nanoplasmonic coupler yielding 67% efficiency

In this paper, we propose a novel ultra-compact nanoplasmonic coupler using gallium lanthanum sulfide (GLS) which yields an efficiency of 67% at the optical communication wavelength. The analysis has been done numerically using the finite-difference time-domain method. Our proposed coupler can operate at a broad frequency range and easier to fabricate than couplers with multi-section tappers since it is a simple rectangular-shaped coupler with no variation along the whole length.