Electrical tunable topological valley photonic crystals for on-chip optical communications in the telecom band

Abstract

On-chip optical communications are in increasingly demand for low-loss, small-footprint and power-efficient waveguiding solutions in the telecom band. However, most integrated optical circuits suffer from high propagation loss and low integration degree. Through manipulating the valley-dependent topological phase of light, we have experimentally demonstrated both robust optical transport and electrical modulation of lightwaves at telecom wavelengths in the valley photonic crystals. With the adoption of valley kink states, the 25 Gbit/s optical signal at 1550 nm is successfully transmitted through a highly twisted interface. Furthermore, an extreme high data rate of 100 Gbit/s is demonstrated with such topological waveguide by wavelength division multiplexing. The electrical tunability of the topological modulators based on thermo-optic effect is also verified, opening a novel route towards active valley kink photonic devices. Our study shows a great possibility of making use of the topological protection in building up high-speed datalinks on a chip.

External defect immune high quality resonances in microwave topological ring resonator

“…Topology, a mathematical concept, deals with the quantities that remain conserved under continuous arbitrary deformation [1]. Extending this mathematical concept to the photonics realm brings about a revolutionary change in both the theoretical and experimental domains of physics and engineering with promising applications in robust delay lines [2][3][4], splitters [5][6][7], reflectionless waveguides [8,9], topological lasers [10,11], active photonic devices [12][13][14] and many * Author to whom any correspondence should be addressed. more [15][16][17].…”

Localization of edge state in acoustic topological insulators by curvature of space

“…In the past several decades, TIs have constituted an expanding research field in condensed matter, and the robust transport effect of boundary states against disorders has attracted intense interest in classical systems [7][8][9][10][11][12]. Inspired by these concepts, analogous topological optics/acoustic are becoming a hot notion throughout physics in a variety of frontier domains [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29], such as one-way propagation [13,14], communications [15,16], and acoustic-noise reduction [17] and so on. Similar to the electrons propagating in a crystal, sound in the phononic crystal will also experience a periodic potential [18][19][20], and the physical performance can be delineated by the energy band structure, such as the concept of topology [21][22][23].…”

Topological edge state assisted dynamically tunable microwave propagations in photonic crystals

“…Therefore, the dynamically tunable topological TPC structures are highly desirable to realize reconfigurable, self-adaptive, and multi-functional photonic devices. Although dynamic tunability has been proposed in 1D and 2D TPC structures based on thermal tuning [26], mechanical tuning [27], optical tuning [28][29][30] as well as electrical tuning [31] for acoustic, terahertz, and communication wavelengths, it is still challenging to achieve amplitude tunable topological photonic devices especially when the devices are composed of metal rods. Therefore, in this work, we experimentally demonstrate a technique of dynamic tunability of EM wave propagation through a TPC structure that would be useful to realize modulators, beam splitters, and many other photonic devices in the microwave regime.…”