An effective density matrix approach for intersubband plasmons coupled to a cavity field: electrical extraction/injection of intersubband polaritons

Abstract

The main technological obstacle hampering the dissemination of modern optoelectronic devices operating with large light-matter coupling strength $\Omega$ is an in-depth comprehension of the carrier current extraction and injection from and into strongly coupled light-matter states, the so-called polaritonic states. The main challenge lies in modeling the interaction between excitations of different nature, namely bosonic excitations (the plasmonic ISB excitations) with fermionic excitations (the electrons within the extraction or injection subband). In this work, we introduce a comprehensive quantum framework that encompasses both the ISB plasmonic mode and the extractor/injector mode, with a specific emphasis on accurately describing the coherent nature of transport. This reveals inherent selection rules dictating the interaction between the ISB plasmon and the extraction/injection subband. To incorporate the dynamics of the system, this framework is combined to a density matrix model and a quantum master equation which have the key property to distinguish intra and intersubband mechanisms. These theoretical developments are confronted to experimental photocurrent measurements from midinfrared quantum cascade detectors ($\lambda$ = 10 $\mu$m) embedded in metal-semiconductor-metal microcavities, operating at the onset of the strong light-matter coupling regime (2$\Omega$ = 9.3 meV). We are able to reproduce quantitatively the different features of the photocurrent spectra, notably the relative amplitude evolution of the polaritonic peaks with respect to the voltage bias applied to the structure. These results on extraction allow us to elucidate the possibility to effectively inject electronic excitations into ISB plasmonic states, and thus polaritonic states.

References in corpus (13)

• Quantum fluids of light
• Optical properties of metal-dielectric-metal microcavities in the THz frequency range
• Intersubband Polaritons in the Electrical Dipole Gauge
• Microcavity polariton light emitting diode
• Charge induced coherence between intersubband plasmons in a quantum structure
• Electroluminescence emission from polariton states in GaAs-based semiconductor microcavities
• Quantum theory of electron tunneling into intersubband cavity polariton states
• Quantum model of microcavity intersubband electroluminescent devices
• Intersubband electroluminescent devices operating in the strong coupling regime
• Optical phonon scattering of cavity polaritons in an electroluminescent device
• Intersubband polariton-polariton scattering in a dispersive microcavity
• Low intensity saturation of an ISB transition by a mid-IR quantum cascade laser
• Resonant Tunneling Diodes Strongly Coupled to the Cavity Field