Cardea, IvanGrassani, DavideUpham, JeremySchulz, Sebastian A.Tsakmakidis, KosmasBrès, Camille Sophie2021-03-012021-03-012021-03-012021-01-1210.1103/PhysRevA.103.013716https://infoscience.epfl.ch/handle/20.500.14299/175599The time-bandwidth limit is a mathematical tenet that affects all reciprocal resonators, stating that the product of the spectral bandwidth that can couple into a resonant system and its characteristic energy decay time is always equal to 1. Here, we develop an analytical and numerical model to show that introducing nonreciprocal coupling to a generalized resonator changes the power balance between the reflected and intracavity fields, which consequently overcomes the time-bandwidth limit of the resonant system. By performing a full evaluation of the time-bandwidth product (TBP) of the modeled resonator, we show that it represents a measure of the increased delay imparted to a light wave, with respect to what the bandwidth of the reciprocal resonant structure would allow to the same amount of in-coupled power. No longer restricted to the value 1, we show that the TBP can instead be used as a figure of merit of the improvement in intracavity power enhancement due to the nonreciprocal coupling.Time-Bandwidth limittime-bandwidth productfigure-9slow lightdelay lineOptical bufferResonatorsResonant Cavitytext::journal::journal article::research article