Ultra-thin curved visible microdisk lasers with three-dimensional whispering gallery modes

Abstract

<jats:title>Abstract</jats:title><jats:p>Microdisk lasers are important components in photonic integrated circuits (PICs), of which the whispering gallery modes (WGMs) are usually confined within a two-dimensional (2D) planar slab. Here, owing to the strain relaxation of quantum wells by wet-etching method, we present ultra-thin curved visible microdisk lasers with single-mode lasing emission and a high quality factor of ∼17,000, which enable a 3D spatial intensity distribution of WGMs and provide an extra degree of freedom for the confined photons compared with the conventional 2D in-plane WGMs. The curved microdisk lasers with a 3D spatial profile of WGMs may provide attractive applications in flexible and multilevel photon sources for the PICs.</jats:p>

Manipulating cavity photon dynamics by topologically curved space

“…In comparison with flat 2D surfaces, curved 2D surfaces can be classified into two categories: the ones that can and cannot be unfolded to become flat surfaces. The former, such as the bent-up microdisks 39 , 40 , is not of our interest as its geodesic lines exactly correspond to the straight lines on the unfolded plane, making no difference in ray dynamics compared to a flat surface. Nevertheless, the latter is much more interesting, as it is formed based on a general definition of topological deformation from a flat surface by keeping the topological invariant, leading to the reconstruction of light trajectories.…”

“…Recently, curved membranes are developed to form three-dimensional (3D) on-chip photonic structures, which would allow the much higher capacity of devices on integrated photonic circuits compared to the two-dimensional (2D) counterparts 37 , 38 . Interestingly, it has been experimentally demonstrated that a 2D microdisk cavity can be bent up to support WGMs exhibiting 3D trajectories in space, while keeping a considerably high-quality factor 39 , 40 . It is therefore interesting to consider if a WGM defined on a curved 2D surface can be efficiently analyzed with both ray dynamics and wave optics, and most significantly, if such structures bring fundamental changes that would potentially lead to a great improvement of device performance and on-chip integration.…”

Characteristics and Thermal Control of Random and Fabry–Pérot Lasing in Nanowire Arrays

“…39 Since the length of the NWs in this sample is ∼4 μm, mode leakage is minimal for random lasing cavities. It is also worth mentioning that considering the very small sizes of the NW cross section in comparison to the lasing wavelength, the irregular polygon shape of the cross section, 49 and tapering of the NWs, the whispering gallery mode (WGM) 50 is very unlikely to be supported in the "RL system". Moreover, the near-field emission profiles reported in our previous work 40 show that the sizes of the modes are much bigger than the size of NW and the emission does not originate from the side of the NW, 51 eliminating any possibility of WGMs.…”

Manipulating cavity photon dynamics by topologically curved space

“…In comparison with flat 2D surfaces, curved 2D surfaces can be classified into two categories: the ones that can and cannot be unfolded to become a flat surface. The former, such as the bent-up microdisks 39,40 , are not of our interest as its geodesic lines exactly correspond to the straight lines on the unfolded plane, making no difference in ray dynamics compared to a flat surface. Nevertheless, the latter is much more interesting, as it is formed based on a general definition of topological deformation from a flat surface by keeping the topological invariant, leading to the reconstruction of light trajectories.…”

“…Recently, curved membranes are developed to form three-dimensional (3D) on-chip photonic structures, which would allow much higher capacity of devices on integrated photonic circuits compared to the two-dimensional (2D) counterparts 37,38 . Interestingly, it has been experimentally demonstrated that a 2D microdisk cavity can be bent up to support WGMs exhibiting 3D trajectories in space, while keeping a considerably high quality factor 39,40 . It is therefore interesting to consider if a WGM defined on a curved 2D surface can be efficiently analyzed with both ray dynamics and wave optics, and most significantly, if such structures bring fundamental changes that would potentially leads to great improvement of device performance and on-chip integration.…”