Ultrastrong Light–Matter Coupling in Deeply Subwavelength THz LC Resonators

Mathieu Jeannin (1) , Giacomo Mariotti Nesurini (1) , Stéphan Suffit (1) , Djamal Gacemi (1) , Angela Vasanelli (1) , Lianhe Li (2) , Alexander Giles Davies (2) , Edmund Linfield (2) , Carlo Sirtori (1) , Yanko Todorov (1)

1 MPQ (UMR_7162) - Laboratoire Matériaux et Phénomènes Quantiques
2 School of Electronic and Electrical Engineering [Leeds]

The ultra-strong light-matter coupling regime has been demonstrated in a novel three-dimensional inductor-capacitor (LC) circuit resonator, embedding a semiconductor two-dimensional electron gas in the capacitive part. The fundamental resonance of the LC circuit interacts with the intersubband plasmon excitation of the electron gas at ω c = 3.3 THz with a normalized coupling strength 2Ω R /ω c = 0.27. Light matter interaction is driven by the quasi-static electric field in the capacitors, and takes place in a highly subwavelength effective volume V eff = 10 −6 λ 3 0. This enables the observation of the ultra-strong light-matter coupling with 2.4 × 10 3 electrons only. Notably, our fabrication protocol can be applied to the integration of a semiconductor region into arbitrary nano-engineered three dimensional meta-atoms. This circuit architecture can be considered the building block of metamaterials for ultra-low dark current detectors.

Domaines: Optique [physics.optics]; Autre [cond-mat.other]; Physique Quantique [quant-ph]

Mathieu Jeannin, Giacomo Mariotti Nesurini, Stéphan Suffit, Djamal Gacemi, Angela Vasanelli, et al.. Ultrastrong Light–Matter Coupling in Deeply Subwavelength THz LC Resonators. ACS photonics, 2019, ⟨10.1021/acsphotonics.8b01778⟩. ⟨hal-02099165⟩