Molecular polariton electroabsorption.

We investigate electroabsorption (EA) in organic semiconductor microcavities to understand whether strong light-matter coupling non-trivially alters their nonlinear optical [[Formula: see text]] response. Focusing on strongly-absorbing squaraine (SQ) molecules dispersed in a wide-gap host matrix, we find that classical transfer matrix modeling accurately captures the EA response of low concentration SQ microcavities with a vacuum Rabi splitting of [Formula: see text] meV, but fails for high concentration cavities with [Formula: see text] meV. Rather than new physics in the ultrastrong coupling regime, however, we attribute the discrepancy at high SQ concentration to a nearly dark H-aggregate state below the SQ exciton transition, which goes undetected in the optical constant dispersion on which the transfer matrix model is based, but nonetheless interacts with and enhances the EA response of the lower polariton mode.

Exceptional point magneto-optic isolators.

We show that operating magneto-optic coupled ring isolators near an exceptional point (EP) fundamentally improves their tradeoff between isolation bandwidth and insertion loss. In analogy to EP sensors, operating a coupled ring isolator at an EP causes its isolation bandwidth to depend on the square root of the nonreciprocal phase shift (NRPS) instead of the usual linear dependence, thereby enhancing the bandwidth when the NRPS is small. In cases of practical interest, this behavior enables more than a 50% increase in 20 dB isolation bandwidth at 3 dB insertion loss for a given pair of rings.

Ultrafast Charge Transfer Dynamics at the Origin of Photoconductivity in Doped Organic Solids.

In spite of their growing importance for optoelectronic devices, the fundamental properties and photophysics of molecularly doped organic solids remain poorly understood. Such doping typically leads to a small fraction of free conductive charges, with most electronic carriers remaining Coulombically bound to the ionized dopant. Recently, we have reported photocurrent for devices containing vacuum-deposited TAPC (1,1-bis(4-bis(4-methylphenyl)aminophenyl)cyclohexane) doped with MoO, showing that photoexcitation of charged TAPC molecules increases the concentration of free holes that contribute to conduction.

Polaron Photoconductivity in the Weak and Strong Light-Matter Coupling Regime.

We investigate the potential for cavity-modified electron transfer in a doped organic semiconductor through the photocurrent that arises from exciting charged molecules (polarons). When the polaron optical transition is strongly coupled to a Fabry-Perot microcavity mode, we observe polaron polaritons in the photoconductivity action spectrum and find that their magnitude depends differently on applied electric field than photocurrent originating from the excitation of uncoupled polarons in the same cavity. Crucially, moving from positive to negative detuning causes the upper and lower polariton photocurrents to swap their field dependence, with the more polaronlike branch resembling that of an uncoupled excitation.

Biodistribution of Viscumin after Subcutaneous Injection to Mice and In Vitro Modeling of Endoplasmic Reticulum Stress.

Viscumin (mistletoe lectin I, MLI) in concentrations of 10-10 M causes endoplasmic reticulum stress and triggers unfolded protein response, a modulator of antitumor immunity, in target cells.