2024-01-15 スイス連邦工科大学ローザンヌ校(EPFL)
Schematic of the experiment. Nonlinear spatiotemporal light patterns in a photonic chip-based microresonator modulate the spectrum of a beam of free electrons in a transmission electron microscope.
Credit: Yang et al. DOI: 10.1126/science.adk2489
◆この手法は、小型フォトニックチップによる高繰り返し率の超高速電子顕微鏡や粒子加速器の実現に向けた新たな可能性を示唆しています。
＜関連情報＞
- https://actu.epfl.ch/news/bridging-light-and-electrons/
- https://www.science.org/doi/10.1126/science.adk2489
マイクロ共振器における非線形光学状態と自由電子の相互作用 Free-electron interaction with nonlinear optical states in microresonators
Yujia Yang,Jan-Wilke Henke,Arslan S. Raja,F. Jasmin Kappert,Guanhao Huang,Germaine Arend,Zheru Qiu,Armin Feist,Rui Ning Wang,Aleksandr Tusnin ,Alexey Tikan,Claus Ropers,and Tobias J. Kippenberg
Science
Editor’s summary
Electron microscopes provide imaging capability on the tiniest of scales. The electron beams that scatter off the samples are generally energetically stable and spatially uniform. Being able to modulate the beam to access spatiotemporal information about the sample would be extremely useful but is technically challenging. Yang et al. demonstrate that the nonlinear optical states induced in a microresonator can interact with the electron beam and imprint the nonlinear optical states onto the beam (see the Perspective by Polman and García de Abajo). This interaction provides access to ultrafast modulation of the electron beam and broadens the application of electron microscopes for spatiotemporal imaging and spectroscopy. —Ian S. Osborne
Abstract
The short de Broglie wavelength and strong interaction empower free electrons to probe structures and excitations in materials and biomolecules. Recently, electron-photon interactions have enabled new optical manipulation schemes for electron beams. In this work, we demonstrate the interaction of electrons with nonlinear optical states inside a photonic chip–based microresonator. Optical parametric processes give rise to spatiotemporal pattern formation corresponding to coherent or incoherent optical frequency combs. We couple such “microcombs” to electron beams, demonstrate their fingerprints in the electron spectra, and achieve ultrafast temporal gating of the electron beam. Our work demonstrates the ability to access solitons inside an electron microscope and extends the use of microcombs to spatiotemporal control of electrons for imaging and spectroscopy.
