Coupling of deterministically activated quantum emitters in hexagonal boron nitride to plasmonic surface lattice resonances

Abstract

Cooperative phenomena stemming from radiation-field-mediated coupling between individual quantum emitters are presently attracting broad interest for on-chip photonic quantum memories and longrange entanglement. Common to these applications is the generation of electro-magnetic modes over macroscopic distances. Much research, however, is still needed before such systems can be deployed in the form of practical devices, starting with the investigation of alternate physical platforms. Quantum emitters in two-dimensional (2D) systems provide an intriguing route because these materials can be adapted to arbitrarily shaped substrates to form hybrid systems where emitters are near-field-coupled to suitable optical modes. Here, we report a scalable coupling method allowing color center ensembles in a van der Waals material -hexagonal boron nitride -to couple to a delocalized high quality plasmonic surface lattice resonance. This type of architecture is promising for photonic applications, especially given the ability of the hexagonal boron nitride emitters to operate as singlephoton sources at room temperature.

Boron nitride for excitonics, nano photonics, and quantum technologies

“…Intentional substitutional doping of hBN with foreign atoms is very much challenging [54], incorporation of C, Si, and Mg have been attempted with moderate fortunes [55]. The bulk material is still particularly rich in different defects, which is fortunate as many of them act as efficient single photon sources [56][57][58][59][60]. They browse a broad energy range from let us say 5.5 eV down to about 1.5 eV and they are on the go towards an identification in terms of "what gives what" [61,62].…”

“…The issue is the doping which still remains routinely unsolved. One important result is the residual p-type doping of hBN [122], most probably due to native defects [53,60].…”

“…By combining direct lattice imaging of hBN with electronic structure calculations, Daichi Kozawa et al [61] have recently proposed an assignment in terms of various declinations of an up to 16-atom triangular defect around a single B vacancy. According to [60], an optical transition where an electron is excited from a doubly occupied boron dangling bond to a localized B p z state is expected to give rise to a zerophonon line of 2.06 eV. This field is very active at the time being both from the experimental and theoretical sides [56][57][58][59][60][61][148][149][150][151][152][153][154][155][156][157].…”

“…According to [60], an optical transition where an electron is excited from a doubly occupied boron dangling bond to a localized B p z state is expected to give rise to a zerophonon line of 2.06 eV. This field is very active at the time being both from the experimental and theoretical sides [56][57][58][59][60][61][148][149][150][151][152][153][154][155][156][157]. Undoubtfully, the quest for a defect with a spin [158] susceptible to challenge the NV centre in diamond [159] or the double vacancy in SiC [160] motivates most of these studies.…”

Defects by design: Quantum nanophotonics in emerging materials

“…These key features are necessary for the use of h-BN's quantum emitters in photonic devices, but they have generally been lacking in samples contaminated by the transfer process. Finally, Proscia et al [13] engineer devices based on ensembles of quantum emitters in h-BN films coupled to surface plasmon resonances in an underlying array of silver nanopillars, demonstrating the ability to tune both the intensity and direction of the emission.…”