Multimode, Aperiodic Terahertz Surface-Emitting Laser Resonators
AbstractQuasi-crystal structures are conventionally built following deterministic generation rules although they do not present a full spatial periodicity. If used as laser resonators, they open up intriguing design possibilities that are simply not possible in conventional periodic photonic crystals: the distinction between symmetric (vertically radiative but low quality factor Q) and anti-symmetric (non-radiative, high Q) modes is indeed here fully overcome, offering a concrete perspective of highly efficient vertical emitting resonators. We here exploit electrically pumped terahertz quantum cascade heterostructures to devise two-dimensional seven-fold quasi-crystal resonators, exploiting rotational order or irregularly distributed defects. By lithographically tuning the lattice quasi-periodicity and/or the hole radius of the imprinted patterns, efficient multimode surface emission with a rich sequence of spectral lines distributed over a 2.9–3.4 THz bandwidth was reached. We demonstrated multicolor emission with 67 mW of peak optical power, slope efficiencies up to ≈70 mW/A, 0.14% wall plug efficiencies and beam profile results of the rich quasi-crystal Fourier spectrum that, in the case of larger rotational order, can reach very low divergence. View Full-Text
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Biasco, S.; Li, L.; Linfield, E.H.; Davies, A.G.; Vitiello, M.S. Multimode, Aperiodic Terahertz Surface-Emitting Laser Resonators. Photonics 2016, 3, 32.
Biasco S, Li L, Linfield EH, Davies AG, Vitiello MS. Multimode, Aperiodic Terahertz Surface-Emitting Laser Resonators. Photonics. 2016; 3(2):32.Chicago/Turabian Style
Biasco, Simone; Li, Lianhe; Linfield, Edmund H.; Davies, A. G.; Vitiello, Miriam S. 2016. "Multimode, Aperiodic Terahertz Surface-Emitting Laser Resonators." Photonics 3, no. 2: 32.
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