Using an ultrafast transmission electron microscope, Technion researchers have,, for the first time, recorded the propagation of combined sound and light waves in atomically thin materials.
OUR NEW TECHNIQUE CAN IMAGE THE MOTION OF LIGHT WITHOUT DISTURBING IT. – Yaniv Kurman, PhD student
At the height of the pandemic lockdown, with the Kaminer lab at Technion City closed, graduate student Yaniv Kurman took his mathematical calculations home, where he predicted how light pulses should behave in 2D materials and how they could be measured. At the same time, fellow student Raphael Dahan realized how to focus infrared pulses into the group’s electron microscope and made the necessary upgrades to accomplish that.
Once lockdown was over, Assoc. Prof. Ido Kaminer’s group met for real and succeeded in proving Kurman’s theory, and even discovered new and unexpected phenomena. The scientists shone pulses of light along the edge of a 2D material, producing hybrid sound-light waves in the material. Not only were they able to record these waves, but they also found the pulses can spontaneously speed up and slow down. Surprisingly, the waves even split into two separate pulses, moving at different speeds. “The hybrid wave moves inside the material, so you cannot observe it using a regular optical microscope,” Kurman explained. “Our results could not have been achieved using existing methods. So, in addition to our scientific findings, we present a previously unseen measurement technique that will be relevant to many more scientific discoveries.”
THIS PRESENTS A REAL BREAKTHROUGH IN ULTRAFAST NANO-OPTICS AND REPRESENTS STATE OF THE ART AND THE LEADING EDGE OF THE SCIENTIFIC FRONTIER. THE OBSERVATION IN REAL SPACE AND IN REAL-TIME IS BEAUTIFUL AND HAS, TO MY KNOWLEDGE, NOT BEEN DEMONSTRATED BEFORE. – Prof. Harald Giessen, University of Stuttart
The discovery, published in Science, revolutionizes the capabilities of electron microscopes and opens the possibility of optical communication through atomically thin layers. “We are planning experiments that will measure vortices of light, experiments in Chaos Theory, and simulations of phenomena that occur near black holes. Moreover, our findings may permit the production of atomically thin fiber-optic “cables”, which could be placed within electrical circuits and transmit data without overheating,” said Kaminer.
The experiments were performed in the Robert and Ruth Magid Electron Beam Quantum Dynamics Laboratory headed by Prof. Ido Kaminer. Team members included Dr. Kangpeng Wang, Michael Yannai, Yuval Adiv, and Ori Reinhardt. Kaminer is a member of the Viterbi Faculty of Electrical and Computer Engineering and the Helen Diller Quantum Center.
