Extending the Self-Discharge Time of Dicke Quantum Batteries Using Molecular Triplets

Abstract

Quantum batteries, quantum systems for energy storage, have gained interest due to their potential scalable charging power density. A quantum battery proposal based on the Dicke model has been explored using organic microcavities, which enable a cavity-enhanced energy-transfer process called superabsorption. However, energy-storage lifetime in these devices is limited by fast radiative emission losses, worsened by superradiance. Here, we demonstrate a promising approach to extend the energy-storage lifetime of Dicke quantum batteries using molecular triplet states. We examine a type of multilayer microcavity where an active absorption layer transfers energy to the molecular triplets of a storage layer, identifying two regimes based on exciton-polariton resonances. We tested one of these mechanisms by fabricating and characterizing five devices across a triplet-polariton resonance, showing that triplet population is maximized when the lower polariton and triplet state are isoenergetic. We found that one of these devices can store energy for 40.3 <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mo>±</a:mo> </a:math> 0.4 <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"> <c:mi>μ</c:mi> <c:mrow> <c:mrow> <c:mi mathvariant="normal">s</c:mi> </c:mrow> </c:mrow> </c:math> , a <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"> <f:msup> <f:mn>10</f:mn> <f:mn>3</f:mn> </f:msup> </f:math> -fold increase in storage time compared to previous demonstrations. We conclude by discussing potential optimization outlooks for this class of devices.

Topics & Concepts