The nonlinear effects and applications of gain doped whispering-gallery mode cavities

Abstract

Whispering gallery mode (WGM) cavities formed by dielectric structures have attracted intensive interest in various fields. The high-quality factor and smaller mode volume associated with the optical modes have inspired experiments in nonlinear optics, nanophotonics, and quantum information science. Moreover, it also gives rise to optical biosensors and other significant applications. To further reduce the material loss of the resonator, optical gain materials, such as erbium and ytterbium, are doped into the dielectric structure to increase the nonlinear effect and enhance the interaction between light and matter. Here in this review, we outline the most recent advancements in gain-doped optical WGM microcavities. Moreover, we introduce the dynamics of the gain in WGM resonators, the integration of gain media into WGM microcavities with various shapes, and the fabrication and applications of the gain microcavities. Also, the applications of the gain cavity based on the whispering-gallery mode have been introduced, e.g., ultra-sensitive sensors, low-threshold lasers, and high-performance optical systems.

Electromagnetically induced grating in a nonlinear optomechanical cavity

“…This effect arises due to quantum interference between distinct excitation pathways in the atomic system, and is referred to as electromagnetically induced transparency (EIT). EIT has found extensive use in the study of light-matter interactions, owing to its noteworthy quantum coherent properties [2][3][4][5][6][7]. EIT is particularly relevant for diverse applications, including slow light [8][9][10], the creation of a significant nonlinear response [11,12], the generation of an electromagnetically induced grating (EIG) [13][14][15][16][17][18] and other related phenomena [5,[19][20][21][22][23][24][25].…”

“…EIT has found extensive use in the study of light-matter interactions, owing to its noteworthy quantum coherent properties [2][3][4][5][6][7]. EIT is particularly relevant for diverse applications, including slow light [8][9][10], the creation of a significant nonlinear response [11,12], the generation of an electromagnetically induced grating (EIG) [13][14][15][16][17][18] and other related phenomena [5,[19][20][21][22][23][24][25]. Recent studies have observed the EIG phenomenon in atomic systems, quantum wells, and quantum dots [26][27][28].…”

Optomechanically induced grating in a graphene based nanocavity

“…indices [10], and others [7,[11][12][13][14] all heavily rely on coherent medium. Using atomic systems, in addition to a single EIT, numerous EIT windows have been seen using a variety of atom-field configurations, including multi-levels atomic media [15][16][17][18][19][20][21]. Since there are many EIT windows, it is possible to transmit light simultaneously at various frequencies, which has potential uses in optical signal processing [22][23][24][25].…”

Using Hocker and Burns numerical method to analyze the dispersion properties of a planar waveguide with an exponentially graded-index core layer for s-polarized light

“…The staircase technique is a very common numerical method that is employed for such cases. In a recent paper, an on-chip Luneburg lens was applied through the integration of gradient Si waveguides and metamaterial structures [16][17][18][19][20][21][22][23]. In order to achieve the gradient index distribution, the filling ratio mapping of Si nanorods was utilized.…”