Researchers have developed a way to create photonic time crystals and have shown that these amazing man-made objects make light shine through them. These discoveries could lead to more efficient and robust wireless communications and better lasers.
Nobel Laureate Frank Wilczek made the first time crystal in 2012. Although natural crystals usually have a structural pattern that repeats in space, in crystal time, the pattern repeats in time. Although some scientists initially doubted the existence of periodic crystals, recent experiments have succeeded in creating them. Last year, researchers at Aalto University’s low-energy laboratory created a time-matched crystal that could be useful for quantum devices.
Now another team has developed (Way to Create Photonic Time Crystals) a photonic time crystal, which is the time analogs of optical devices. The researchers created a photonic time crystal that works at microwave frequencies, and they proved that the crystal can amplify electromagnetic waves. This capability has potential applications in a variety of technologies, including wireless communications, integrated circuits, and lasers.
Until now, research on photonic phase crystals has focused on bulk materials, i.e. three dimensions. This is very difficult, and the experiments did not go beyond the model process without practical applications. Now a team including researchers from Aalto University, Karlsruhe Institute of Technology (KIT) and Stanford University have tried a new approach: build a two-dimensional photonic time crystal.
“We found that reducing the dimensions from a 3D structure to a 2D structure made it easier to implement, making it possible to realize photonic time crystals in reality,” said Xuchen Wang, the lead researcher of the study says, is a PhD student in Aalto and is currently at KIT.
The new method allowed the team to create a photonic crystal phase and use it to analyze predictions about its behavior. “We have demonstrated for the first time that photonic phase crystals can increase the incident light with great value,” Wang says.
“In a photonic crystal, the photons are arranged in a pattern that repeats over time. This means that the photons in the crystal interact and overlap, which can lead to interference. Useful in the increase of heat,” says Wang.
Two-dimensional photonic phase crystals have many potential applications. By amplifying electromagnetic waves, they can make transmitters and receivers more powerful or more efficient. Wang pointed out that coatings on 2D photonic phase crystals can also help with decay, which is a major problem in wireless transmission. Photonic phase crystals can also simplify laser design by eliminating the need for large mirrors commonly used in laser beams.
Another application emerges from the discovery that 2D phase photonic crystals not only pick up electromagnetic waves that hit them in space, but also waves that travel in the opposite direction. Surface waves are used for communication between electronic components and integrated circuits.
“As a wave propagates, it experiences material loss and signal strength decreases. With 2D Photonic Time Crystals installed in the system, the wavelength can be increased and communication performance can be improved,” said Professor Viktar Asadchy, who developed the concept of 2D Photonic Time Crystals.
Source: Aalto University.
