Tamm Plasmon--Enhanced Widely Tunable Near-Infrared Nanolaser with Superior Efficiency and Output Power
Mohammad Tahsin Alam, Zafrin Jahan Nikita, Ying Yin Tsui, Md. Zahurul Islam
TL;DR
This work presents a room-temperature, widely tunable near-infrared plasmonic nanolaser that leverages optical Tamm states at a metal–DBR interface and extraordinary optical transmission through an octagonal nanohole array. A dual-DBR feedback scheme dramatically boosts forward emission and directionality while suppressing backward leakage, achieving a high integrated output and a narrow far-field beam (divergence around $0.631^\circ$). Tunability is realized by adjusting the terminating and gain-layer thicknesses and the number of top-DBR layers, enabling emission from roughly $850$ to $945$ nm with a notably reduced pump threshold of $2.8\times10^{7}$ V/m ($0.0031$ mJ cm$^{-2}$). The combination of TP excitation, EOT coupling, and dual-DBR feedback offers a cost-effective, scalable platform for on-chip photonics and quantum technologies, with substantial gains in output power and efficiency over single-DBR configurations.
Abstract
Plasmonic resonances enable strong electromagnetic field confinement and have been widely exploited in plasmonic nanolasers, particularly through surface plasmon polaritons and localized surface plasmons. However, their performance is often limited by bidirectional output coupling and multimode far-field emission, primarily due to higher-order diffraction arising from these modes. In this work, we utilize the Tamm plasmon resonance to realize lasing in the NIR region with wide tunability. The optical Tamm states are excited at the metal-DBR interface by an incident pump pulse and their emission intensity is significantly enhanced via extraordinary optical transmission through a metallic nanohole array. The subwavelength periodicity of the nanohole array restricts the emission to the zeroth order, resulting in a highly directional far-field pattern with a full width at half maximum of approximately 0.631 degrees. To further improve performance, a second DBR is incorporated beneath the pump side, which substantially suppresses backward emission around the lasing wavelength and enhances forward lasing intensity by around 1.3 X 10^4 times, thus increasing the integrated emission power. The combination of Tamm plasmon excitation and dual-DBR feedback significantly improves the cavity's optical response and overall lasing efficiency. Additionally, we have demonstrated lasing at 870 nm with a reduced pump threshold of 2.8 X 10^7 V/m (energy of 0.0031 mJ/cm^2). Moreover, a broad tunability in lasing wavelength, spanning from 850 nm to 944.5 nm, is achieved. These results demonstrate a cost-effective and versatile strategy for plasmonic nanolasers with enhanced output power, low reflection-side loss, wide tunability, and strong integration potential for on-chip photonic and quantum technologies.