Nanocavity‐Based Determination of Absolute Values of Photoluminescence Quantum Yields

Abstract

We present a new method for determining absolute values of quantum yield of luminescent emitters, which is based on the modification of the radiative transition of emitters within a tunable metallic nanocavity. The method presented is easy to set up and works without any calibration. It will thus be useful for all applications where absolute and calibration-free measurements of luminescence quantum yields are needed. Moreover, it requires only a minute amount of low-concentration fluorophore solution. We give a detailed description of the theory and data evaluation of the nanocavity measurements, and report experimental results for several common dyes in aqueous solution.

Revealing the radiative and non-radiative relaxation rates of the fluorescent dye Atto488 in a λ/2 Fabry–Pérot-resonator by spectral and time resolved measurements

“…The impact on the spectral behavior of the cavity embedded fluorophore is in agreement with several previous studies such as the spectral shaping and the modification of the radiative decay rate. 23,28,47 Additionally, the behavior of the nonradiative rate is in accordance with the results of other studies. 9,48-50 A major difference between our photonic microresonators and plasmonic nanoantennas is the separation of the molecules from the metal.…”

“…8 On the other side, a quantum emitter can also be perturbed by optical far-fields of e.g. lasers, 19 resonators via the Purcell effect [20][21][22][23] or electric fields. 24,25 However, in order to sense or control the fluorescence properties of molecules, one requires both, the intrinsic properties of the emitter and the optical properties of the external perturbation 26 determined by the local density of optical states (LDOS).…”

Photoluminescence of a single quantum emitter in a strongly inhomogeneous chemical environment

“…Placing SiO 2 NPs between the metal mirrors of a nanocavity changes their emission behavior due to a cavity-modified electromagnetic field mode density 8,30,31 . Because the cavity changes only the radiative rate of the embedded emitters, measuring the modulation of the PL lifetime as a function of the cavity length allows for determining an absolute value of an emitters' QY 32 . Moreover, as the method is based on the cavityinduced lifetime modulation, it excludes the non-emitting (darkstate) species from the measurement.…”

Single‐Molecule Metal‐Induced Energy Transfer (smMIET): Resolving Nanometer Distances at the Single‐Molecule Level

“…The near-field coupling of an emitting electric dipole (fluorescing molecule) and a planar multilayered substrate has been described many times in several publications, see for example, refs. [32][33][34]. In short, the emitting molecule is considered as an ideal oscillating electric dipole.…”