Lithium Niobate on Insulator: An Emerging Platform for Integrated Quantum Photonics

Abstract

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adom.202100789.

Spectral control of nonclassical light using an integrated thin-film lithium niobate modulator

“…Due to the low voltage requirement of the modulator, it becomes possible to drive multiple V π with readily available RF sources, which in turn enabled us to achieve terahertz-scale (± 641 GHz or ± 5.2 nm) frequency shifts-the largest EO shifting demon- strated to date-along with an 18-fold bandwidth compression through spectral shearing and time lensing, respectively. Our results show a substantial performance breakthrough, and hold great promise for future largescale, multi-functional integration with other essential classical and quantum components that have already been developed on the TFLN platform [28,31].…”

“…In summary, we have demonstrated high-performance electro-optic single-photon spectral shearing and bandwidth compression using an integrated TFLN phase modulator. Besides outstanding performance, a major advantage of our approach is its integrability with other essential components on the TFLN platform [28,31], such as sources [38,39], detectors [40], memories [41], and a complete set of linear optical components [28], for realizing complex photonic circuits and functionalities. By cascading multiple modulators and dispersion units, which may be implemented using dispersion-engineered waveguides or integrated wavelength division multiplexer (WDM) followed by a bank of phase shifters, one may effectively replace the bulk waveshaper and achieve arbitrary spectral control of light fully on-chip.…”

On-Chip Optical Beam Manipulation with an Electrically Tunable Lithium-Niobate-on-Insulator Metasurface

“…Numerous materials, such as silicon, silicon nitride, and indium phosphide, can be employed as platforms [ 1 ]. However, lithium niobate (LN) is under the spotlight because of its large transparency window, large refractive index, strong second-order nonlinearity, and strong electro-optic effect [ 2 ]. LN has become a competitive material in integrated photonics [ 3 ].…”

“…Similar to silicon on insulator, LNOI consists of a substrate made from silicon or LN, on top of which there is a sub-micrometer-thick LN film on a silica buried layer [ 6 ]. With the commercialization of LNOI substrates in recent years, large-scale LNOI substrates have provided an excellent platform for integrated photonics, which greatly promotes the research and development of on-chip integrated photonics [ 2 ]. LNOI has become a rapidly growing and highly promising integrated photonic platform [ 6 ].…”

“…Because of the electro-optic effect in LN, which allows the refractive index to vary upon application of an electric voltage, on-chip electrically tunable devices have been widely reported [ 1 , 15 , 16 ]. Moreover, because LNOI has the structure of a sub-micrometer LN on top of silica, it has a larger refractive index contrast and higher field confinement, making it an excellent electrically tunable platform [ 2 ]. Electrically tunable devices can perform functions in several cases.…”