[Press Release]Time-Correlated Electron and Photon Counting Microscopy　-Nanoscale Emission Lifetime Measurement by Counting Individual Accelerated Electron and Photon Pairs-

​Main points

• Nanoscale emission lifetime measurement in electron microscopy is achieved without pulsing the electron beam for the emission excitation.
• Using individual electrons emitted from a conventional electron gun as excitation pulses, the time correlation between the photons from the sample and accelerated electrons that excite the photons can be obtained.
• This opens up the observation of emission dynamics and the application of quantum technology using entanglement between different quantum particles.

 Overview

​A research group consisting of, a PhD student Mr. Sotatsu Yanagimoto, Researcher Dr. Naoki Yamamoto, Associate Professor Takumi Sannomiya at Tokyo Institute of Technology, Associate Professor Tatsuro Yuge at Shizuoka University, Associate Professor Hikaru Saito at Kyushu University, and Keiichirou Akiba, Principal Researcher at Takasaki Institute for Advanced Quantum Science, National Institutes for Quantum Science and Technology, has succeeded in measuring the emission lifetime (1) of materials at the nanoscale, where the group has employed time correlation between accelerated electrons and photons produced by electron-beam excitation (cathodoluminescence (2)) by using individual electrons as excitation pulses.

The newly developed electron-photon correlation electron microscopy enables not only the observation of emission dynamics with electron beam resolution far exceeding the diffraction limit of light, but also the evaluation of correlation parameters that can extract the effect of quantum entanglement between accelerated electrons and emitted photons. Since each electron emitted from a conventional electron source is used as an excitation pulse, active pulsing of the electron beam, which involves complex and expensive systems, is not required for this novel microscopy. The result opens up the observation of light emission dynamics at the nanoscale and the applications of quantum technology with entanglement between different quantum particles.

This work was published in Springer Nature Communications Physics on September 20, 2023.

Glossary

​(1)Emission lifetime:

A representative interval between the excitation of the electron in a material and its relaxation by emitting a photon. Emission lifetime determines the performance of light-emitting materials, such as LEDs and laser diodes, and is also used to measure various factors, such as pH and local temperature in living organisms.

(2)Cathodoluminescence: 

Photon emission excited by accelerated electrons. Cathode-ray tube displays (CRT) have been the popular application of cathodoluminescence.

Dissertation Information

Publications: Communications Physics

Title: Time-correlated electron and photon counting microscopy

Authors: Sotatsu Yanagimoto, Naoki Yamamoto, Tatsuro Yuge, Hikaru Saito, Keiichirou Akiba, Takumi Sannomiya

DOI:10.1038/s42005-023-01371-1​