Organic Photodiodes with an Extended Responsivity Using Ultrastrong Light–Matter Coupling

Abstract

In organic photodiodes (OPDs) light is absorbed by excitons, which dissociate to generate photocurrent. Here, we demonstrate a novel type of OPD in which light is absorbed by polaritons, hybrid light-matter states. We demonstrate polariton OPDs operating in the ultra-strong coupling regime at visible and infrared wavelengths. These devices can be engineered to show narrow responsivity with a very weak angle-dependence. More importantly, they can be tuned to operate in a spectral range outside that of the bare exciton absorption. Remarkably, we show that the responsivity of a polariton OPD can be pushed to near infrared wavelengths, where few organic absorbers are available, with external quantum efficiencies exceeding those of a control OPD.

Ultrastrong coupling between light and matter

“…The USC regime has also been realized at room temperature at a variety of optical frequencies, coupling cavity photons (or, in one case, plasmons [112]) to Frenkel molecular excitons [16,17,[113][114][115][116][117][118]. These systems consist of thin films of organic molecules with giant dipole moments (which make it possible to reach USC) sandwiched between metal mirrors [see Fig.…”

“…A vacuum Rabi splitting beyond 1 eV, corresponding to η = 0.3, has been reported [16,117]. Using such high coupling strengths, monolithic organic light emitting diodes (OLED) working in the USC regime have been made [16,17,115,116,118]. These devices exhibit a room-temperature dispersionless angle-resolved electroluminescence with very narrow emission lines that can be exploited to realize innovative optoelectronic devices.…”

Dynamics and spectroscopy of molecular ensembles in a lossy microcavity

“…[1][2][3][4][5][6][7][8][9] This has lead to the proposal, development and improvement of technological applications at the crossroads of chemistry, materials science and photonics, with examples ranging from energy and charge transport in the material part 7,[10][11][12][13] to applications in which the photonic characteristics of the hybrid system play the prominent role. [14][15][16][17] The theoretical description of polaritonic systems has rapidly evolved in the past years, from treating the material part as a two-level system (atom) in the framework of the Jaynes-Cummings 18 or Tavis-Cummings 19 Hamiltonian, to including molecular Hamiltonians via i.e. polaritonic potential energy surfaces 20 (pPES) or in the basis of the field-free rovibronic states for spectroscopic properties, 21 quantum electrodynamics density functional theory 22,23 (QEDFT), extensions of the exact factorization approach [24][25][26] and approaches based on wave-packet propagation methods.…”

Controlling the nonadiabatic electron-transfer reaction rate through molecular-vibration polaritons in the ultrastrong coupling regime

“…In this paper, we extend the investigation of the effect of vibrational polariton on the chemical reaction rate to the so-called ultrastrong coupling regime, where the molecule-cavity coupling strength is comparable in magnitude with both the vibrational and the cavity frequencies 44 . The ultrastrong coupling has already been realized in various kinds of systems including intersubband polaritons 45,46 , superconducting circuits 47,48 , Landau polaritons 49,50 , optomechanics 51 as well as organic molecules [52][53][54][55][56][57][58][59] . In particular, the ultrastrong coupling between molecular vibrations and the cavity field has been realized in the experiment of ref.…”