니오븀산리튬 칩 1B

이 칩은 손톱만한 크기로 니오브산리튬 박막 위에 만들어졌으며 환경 변화에 민감해 데이터 통신(인터넷)이나 생물학적 센싱에 활용될 수 있다. 크레딧: RMIT 대학교

이 분야의 선도적인 과학자들은 극도로 얇은 니오브산 리튬 칩이 광 기반 기술에서 실리콘 칩을 능가할 것이라고 예측합니다. 이 칩은 지구에서 먼 거리에서 잘 익은 과일을 감지하는 것부터 달에서의 탐색 안내에 이르기까지 광범위한 잠재적 응용 분야를 가지고 있습니다.

과학자들에 따르면, 니오브산 리튬의 인공 결정은 우수한 성능과 제조 기술의 발전으로 인해 이러한 기술에 선호되는 플랫폼입니다.

RMIT 대학의 Arnan Mitchell 저명한 교수와 애들레이드 대학교의 Andy Boes 박사는 이 글로벌 전문가 팀을 이끌고 사이언스 저널에서 니오브산 리튬의 기능과 잠재적 응용 분야를 검토했습니다.

중국 북경 대학의 과학자들을 포함한 국제 팀과 하버드 대학교 미국에서는 이번 10년 후반에 로버가 달에서 운전할 수 있도록 계획된 내비게이션 시스템을 만들기 위해 업계와 협력하고 있습니다.

니오브산리튬 칩

이 칩은 손톱만한 크기로 니오브산리튬 박막 위에 만들어진다. 인터넷을 더 빠르게 만드는 통신을 포함하여 다양한 응용 분야에서 사용할 수 있습니다. 크레딧: RMIT 대학

글로벌 포지셔닝 시스템을 사용할 수 없기 때문에([{” attribute=””>GPS) technology on the Moon, navigation systems in lunar rovers will need to use an alternative system, which is where the team’s innovation comes in.

By detecting tiny changes in laser light, the lithium-niobate chip can be used to measure movement without needing external signals, according to Mitchell.

“This is not science fiction – this artificial crystal is being used to develop a range of exciting applications. And the competition to harness the potential of this versatile technology is heating up,” said Mitchell, Director of the Integrated Photonics and Applications Centre.

He said while the lunar navigation device was in the early stages of development, the lithium niobate chip technology was “mature enough to be used in space applications”.

“Our lithium niobate chip technology is also flexible enough to be rapidly adapted to almost any application that uses light,” Mitchell said.

“We are focused on navigation now, but the same technology could also be used for linking the internet on the Moon to the internet on Earth.”

What is lithium niobate and how can it be used?

Lithium niobate is an artificial crystal that was first discovered in 1949 but is “back in vogue”, according to Boes.

“Lithium niobate has new uses in the field of photonics – the science and technology of light – because unlike other materials it can generate and manipulate electromagnetic waves across the full spectrum of light, from microwave to UV frequencies,” he said.

“Silicon was the material of choice for electronic circuits, but its limitations have become increasingly apparent in photonics.

“Lithium niobate has come back into vogue because of its superior capabilities, and advances in manufacturing mean that it is now readily available as thin films on semiconductor wafers.”

A layer of lithium niobate about 1,000 times thinner than a human hair is placed on a semiconductor wafer, Boes said.

“Photonic circuits are printed into the lithium niobate layer, which are tailored according to the chip’s intended use. A fingernail-sized chip may contain hundreds of different circuits,” he said.

How does the lunar navigation tech work?

The team is working with the Australian company Advanced Navigation to create optical gyroscopes, where laser light is launched in both clockwise and anticlockwise directions in a coil of fiber, Mitchell said.

“As the coil is moved the fiber is slightly shorter in one direction than the other, according to Albert Einstein’s theory of relativity,” he said.

“Our photonic chips are sensitive enough to measure this tiny difference and use it to determine how the coil is moving. If you can keep track of your movements, then you know where you are relative to where you started. This is called inertial navigation.”

Potential applications closer to home

This technology can also be used to remotely detect the ripeness of fruit.

“Gas emitted by ripe fruit is absorbed by light in the mid-infrared part of the spectrum,” Mitchell said.

“A drone hovering in an orchard would transmit light to another which would sense the degree to which the light is absorbed and when fruit is ready for harvesting.

“Our microchip technology is much smaller, cheaper, and more accurate than current technology and can be used with very small drones that won’t damage fruit trees.”

Next steps

Australia could become a global hub for manufacturing integrated photonic chips from lithium niobate that would have a major impact on applications in technology that use every part of the spectrum of light, Mitchell said.

“We have the technology to manufacture these chips in Australia and we have the industries that will use them,” he said.

“Photonic chips can now transform industries well beyond optical fiber communications.”

Reference: “Lithium niobate photonics: Unlocking the electromagnetic spectrum” by Andreas Boes, Lin Chang, Carsten Langrock, Mengjie Yu, Mian Zhang, Qiang Lin, Marko Lončar, Martin Fejer, John Bowers and Arnan Mitchell, 6 January 2023, Science.
DOI: 10.1126/science.abj4396