TOWARDS TAMSELS: TAMM ASSISTED METASURFACE EMITTING LASERS

Abstract

Optical fibres girdle the earth: information securely travels around the world at the speed of light through optical fibres, supporting modern prosperity. However, this prosperity is at risk due to the "capacity crunch," which refers to the fundamental limitations on the amount of information that can be transmitted through optical fibres. The bottleneck arises from the conversion of electrical signals to optical signals, which restricts the speed at which information can be encoded. In order to overcome these challenges, we need new, compact, and efficient light sources that can be incorporated into photonic and electrical integrated circuits.

These light sources should be able to operate at different wavelengths for WDM, various polarizations, and orbital angular momentum states. Our proposal involves the use of Tamm states, which are topologically protected optical states that can be formed at the surface of a semiconductor-distributed Bragg reflector and a thin (~10nm) metal layer. These states are topologically protected, and by using microscale patterning of the metal, we can create single-mode zero-dimensional confined structures. These structures have already been used to demonstrate lasers and single photon sources at short (<1µm) wavelengths. Our project aims to advance Tamm technology to create innovative light sources using quantum wells. We plan to develop dual-wavelength LEDs and lasers that can operate in the C-band, enabling various photonics applications and all-optical switching. Additionally, we aim to extend the Tamm cavity to increase the gain. We will explore using GaAs/AlGaAs DBR in the Tamm to pave the way for an electrically pumped Tamm laser.