Indexed on: 04 May '17Published on: 04 May '17Published in: Nano Letters
The ability to control the energy flow of light at the nanoscale is fundamental to modern communication and big-data technologies, as well as quantum information processing schemes. However, because photons are diffraction-limited, efforts of confining them to dimensions of integrated electronics have so far proven elusive. A promising way to facilitate nanoscale manipulation of light is through plasmon polaritons-coupled excitations of photons and charge carriers1-5. These tightly confined hybrid waves can facilitate compression of optical functionalities to the nanoscale, but suffer from huge propagation losses that limit their use to mostly subwavelength scale applications. With only weak evidence of macroscale plasmon polaritons propagation has recently been reported theoretically and indirectly6-9, no experiments so far have directly resolved long range propagating optical plasmon polaritons in real space. Here, for the first time to our knowledge, we launch and detect optical plasmon - polaritons, efficiently propagating for record distances in a wireless link based on nanoplasmonic transceivers. We use a combination of near-field scanning probe microscopies to provide high resolution real-space images of the plasmon fields, and explore the propagating field structure. We design our nanotransceiver based on new high-performances nanoantenna, Plantenna10, and channel plasmon waveguide with channel crossection of 20nmX20nm and observe plasmon propagation for distances 1000 times bigger than the plasmon wavelength. We exploit the unique Plantenna architecture to accurately couple the propagating plasmons in the waveguide to surface waves, and efficiently reconvert them to plasmons at the receiver. This successful alliance between Plantenna and channel waveguides enables the design of new generations of optical wireless interconnects, active surface plasmon nano lasers and expedites real long range interaction between quantum emitters and photo - molecular devices.