On-chip erbium-doped lithium niobate microcavity laser

November 30, 2020

As a complement to silicon-based photonic chips, lithium niobate thin film (LNOI) has become a research hotspot in the field of optoelectronic integration due to its outstanding nonlinear, electro-optic, acousto-optic, piezoelectric and other physical properties. On-chip integrated frequency multipliers, modulators, and filters based on lithium niobate thin films have been developed, but the on-chip integrated communication band light source is still in urgent need of development. Recently, researchers from Shanghai Jiao Tong University publicly reported for the first time that they designed, fabricated, and realized the laser output of a microcavity on a lithium niobate chip on a self-developed erbium-doped LNOI.

The whispering gallery mode microdisk resonator has a small size and high quality factor. By selecting a suitable pump source and designing and fabricating the LNOI microdisk carefully, the integrated lithium niobate on-chip C-band lasers output has been achieved. The research results were entitled "On-chip Erbium-doped lithium niobate microcavity laser" and published on October 30, 2020, in SCIENCE CHINA Physics, Mechanics & Astronomy as the cover article of Volume 64, Issue 3. Professors Yuping Chen and Xianfeng Chen from Shanghai Jiao Tong University are the corresponding authors.

As we all know, the energy level system of rare earth erbium ions can meet the conditions of laser radiation in the communication band. Previously, lasers and amplifiers doped with rare-earth ions could only be effectively realized and applied in optical fibers and silica films. So far, there are only a few research reports on erbium-doped lithium niobate thin films, and the fluorescence output is obtainable only at low doping concentrations but with poor uniformity by ion implantation and thermal diffusion methods. When discovering these problems over the past two years, researchers abandoned ion implantation and thermal diffusion methods, and chose to dope erbium ions during the growth of lithium niobate crystals, aiming to solve the problems of erbium-doped lithium niobate concentration and uniformity. As a result, lithium niobate thin films were made via the smart-cut process, as shown in Figure 1. These processes were completed through cooperation with Shanghai Daheng Optical and Fine Mechanics Co., Ltd. and Jinan Jingzheng Electronics Co., Ltd.. The erbium-doped lithium niobate film prepared by this method has a uniform distribution of erbium ions and meets the development requirements of on-chip lasers.

Subsequently, the researchers used a focused ion beam (FIB) etching method to fabricate a microdisk resonator on a 600 nm thick Z-cut erbium-doped lithium niobate film. The pump light in 980 nm and 1480 nm band was used and coupled through a tapered fiber. The laser output in the communication band was obvious under these two pumps (as shown in Figures 2 and 3).

This research result realizes the integrated light source in the communication band of the lithium niobate chip, which is of great significance for the efficient integration of the on-chip light source and various functional devices of the lithium niobate thin film material in the future.
-end-
This research was funded by the National Key R & D Program of China (Grant Nos. 2019YFB2203500?and 2017YFA0303700), National Natural Science Foundation of China (Grant No. 91950107), Foundation for Development of Science and Technology of Shanghai (Grant No. 17JC1400400).

See the article:

Yi'an Liu, Xiongshuo Yan, Jiangwei Wu, Bing Zhu, Yuping Chen, and Xianfeng Chen, On-chip erbium-doped lithium niobate microcavity laser, Sci. China-Phys. Mech. Astron. 64, 234262 (2021), https://doi.org/10.1007/s11433-020-1625-9

https://engine.scichina.com/publisher/scp/journal/SCPMA/64/3/10.1007/s11433-020-1625-9?slug=fulltext

Science China Press

Related Erbium Articles from Brightsurf:

On-chip erbium-doped lithium niobate microcavity laser
Researchers developed a 1-mol% erbium-doped LN crystal and its LNOI on the silicon substrate, and fabricated an erbium-doped LNOI microdisk with a high quality factor (~1.05x10^5).

A new spin on atoms gives scientists a closer look at quantum weirdness
A team of researchers has developed a new way to control and measure atoms that are so close together no optical lens can distinguish them.

Polarimetric parity-time-symmetric photonic system
Parity-time symmetry (PT), rooting in quantum field theory, are now shining in photonic systems.

Scientists provide new explanation for the far side of the Moon's strange asymmetry
The Earth-Moon system's history remains mysterious. Scientists believe the two formed when a Mars-sized body collided with the proto-Earth.

Cell membrane proteins imaged in 3D
A team of scientists including researchers at the National Synchrotron Light Source II have demonstrated a new technique for imaging proteins in 3D with nanoscale resolution.

Enhanced 1.54 μm PL and EL on a perfluorinated Er3+ complex sensitized by an Ir3+ complex
The potential of using erbium-contained organic materials to develop cost-effective electrically-driven light-emitting devices for silicon photonics is well proposed, but methods to increase the power efficiency are keenly sought.

Russian scientists have found a way to make laser optics more effective and cheaper
The research team of the IKBFU developed a fundamentally new method of manufacturing laser optics, which is based on the use of rare-earth metal ions of ytterbium and its oxide.

New system transmits high-speed unrepeated signal over 520 kilometers
Researchers from the Moscow Institute of Physics and Technology have partnered up with engineers from Corning Inc., US, and T8, Russia, and developed a system for high-throughput data transfer over great distances without the need for signal repeating along the way.

NUS researchers use light from nanoparticles to intricately control biological processes
Researchers from the National University of Singapore have developed a method to give more control to optogenetics, by using specially designed nanoparticles and nanoclusters (dubbed 'superballs').

Nanoparticles could someday give humans built-in night vision
Movies featuring heroes with superpowers are all the rage. But while these popular characters are mere flights of fancy, scientists have used nanoparticles to confer a real superpower on ordinary mice: the ability to see near-infrared light.

Read More: Erbium News and Erbium Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.