An arrayed nanoantenna for broadband light emission and detection

Early View publication on wileyonlinelibrary.com (issue and page numbers not yet assigned; citable using Digital Object Identifier – DOI) 1 Introduction The field of optical nanoantennas [1, 2] is currently one of the most developing in plasmon-ics due to their ability to overcome the size and impedance mismatch between subwavelength emitters and free space radiation [3]. Recent studies have demonstrated that the application of radio-frequency (RF) antenna design principles [4, 5] to optical nanoantennas enriches dramatically their functionality and provides novel opportunities for quantum communication [6], subwavelength light enhancement , sensing, medicine and photovoltaic applications [1, 2]. Typically, the radiation of quantum emitters (such as quantum dots [7] or colour centres in nanodiamonds [8]) can be strongly enhanced and highly directed by coupling an emitter to optical Yagi–Uda nanoantennas [9–12]. According to the principle of reciprocity, such kind of antennas can also effectively detect an incoming radiation. Yagi–Uda-like architectures bring considerable advantages over various optical antenna designs [1, 2], which include high antenna gain and directionality originated from the use of inductively and capacitively detuned elements with regard to an active feed [4]. However, in their sim