Nonlinear polaritons in a monolayer semiconductor coupled to optical bound states in the continuum

• 作者: Vasily Kravtsov Ekaterina Khestanova Fedor A.Benimetskiy Tatiana Ivanova Anton K.Samusev Ivan S.Sinev Dmitry Pidgayko Alexey M.Mozharov Ivan S.Mukhin Maksim S.Lozhkin Yuri V.Kapitonov Andrey S.Brichkin Vladimir D.Kulakovskii Ivan A.Shelykh Alexander I.Tartakovskii Paul M.Walker Maurice S.Skolnick Dmitry N.Krizhanovskii Ivan V.Iorsh
• 来源期刊: 光：科学与应用（英文版）
• 年，卷（期）: 2020,（3）
• 所属期刊栏目: Letters
• 页码范围: 491-498
• 页数: 8页
• 语种: 英文

摘要

Optical bound states in the continuum (BICs) provide a way to engineer very narrow resonances in photonic crystals. The extended interaction time in these systems is particularly promising for the enhancement of nonlinear opticalprocesses and the development of the next generation of active optical devices. However, the achievable interaction strength is limited by the purely photonic character of optical BICs. Here, we mix the optical BIC in a photonic crystal slab with excitons in the atomically thin semiconductor MoSe2 to form nonlinear exciton-polaritons with a Rabi splitting of 27 meV, exhibiting large interaction-induced spectral blueshifts. The asymptotic BIC-like suppression of polariton radiation into the far field toward the BIC wavevector, in combination with effective reduction of the excitonic disorder through motional narrowing, results in small polariton linewidths below 3 meV. Together with a strongly wavevector-dependent Q-factor, this provides for the enhancement and control of polariton–polariton interactions and the resulting nonlinear optical effects, paving the way toward tuneable BIC-based polaritonic devices for sensing, lasing, and nonlinear optics.