Four-Port Resonant Tunnelling Bottle Microresonator Device

The phenomenon of resonant tunnelling has attracted significant interest due to its intriguing underlying physics and multidisciplinary applications in the theory of nuclear reactions [1], electron propagation through semiconductor devices, quantum wire and quantum dot structures [2, 3], as well as propagation of light through optical microresonators [4–6]. The applications of resonant tunnelling phenomenon in microresonator photonics is of special interest. The simplest photonic device exhibiting resonant tunnelling behaviour consists of an optical microresonator and two semi-infinite waveguides separated from the microresonator by effective potential barriers, which can be fabricated inside the photonic crystals. In order to observe a similar type of resonant tunnelling in a whispering gallery mode microresonator, the latter should be evanescently coupled to two microfibers, i.e., present a four-port device [5, 6].