Details

Autor(en) / Beteiligte

• Duan, Jiahua
• Alfaro‐Mozaz, Francisco Javier
• Taboada‐Gutiérrez, Javier
• Dolado, Irene
• Álvarez‐Pérez, Gonzalo
• Titova, Elena
• Bylinkin, Andrei
• Tresguerres‐Mata, Ana Isabel F.
• Martín‐Sánchez, Javier
• Liu, Song
• Edgar, James H.
• Bandurin, Denis A.
• Jarillo‐Herrero, Pablo
• Hillenbrand, Rainer
• Nikitin, Alexey Y.
• Alonso‐González, Pablo

Titel

Active and Passive Tuning of Ultranarrow Resonances in Polaritonic Nanoantennas

Ist Teil von

• Advanced materials (Weinheim), 2022-03, Vol.34 (10), p.e2104954-n/a

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2022

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Optical nanoantennas are of great importance for photonic devices and spectroscopy due to their capability of squeezing light at the nanoscale and enhancing light–matter interactions. Among them, nanoantennas made of polar crystals supporting phonon polaritons (phononic nanoantennas) exhibit the highest quality factors. This is due to the low optical losses inherent in these materials, which, however, hinder the spectral tuning of the nanoantennas due to their dielectric nature. Here, active and passive tuning of ultranarrow resonances in phononic nanoantennas is realized over a wide spectral range (≈35 cm−1, being the resonance linewidth ≈9 cm−1), monitored by near‐field nanoscopy. To do that, the local environment of a single nanoantenna made of hexagonal boron nitride is modified by placing it on different polar substrates, such as quartz and 4H‐silicon carbide, or covering it with layers of a high‐refractive‐index van der Waals crystal (WSe2). Importantly, active tuning of the nanoantenna polaritonic resonances is demonstrated by placing it on top of a gated graphene monolayer in which the Fermi energy is varied. This work presents the realization of tunable polaritonic nanoantennas with ultranarrow resonances, which can find applications in active nanooptics and (bio)sensing. Near‐field nanoscopy monitors active and passive tuning of ultranarrow resonances in phononic nanoantennas over a wide spectral range (−35 cm−1, being the resonance linewidth ≈9 cm−1). Passive tunability can be realized by tailoring the dielectric environment of nanoantennas made of boron nitride, while reversible in situ tuning of narrow resonances is realized by placing nanoantennas on top of a graphene layer.