{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:26:05Z","timestamp":1760149565607,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,8,27]],"date-time":"2023-08-27T00:00:00Z","timestamp":1693094400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51727901"],"award-info":[{"award-number":["51727901"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Ultrafast electron diffraction (UED) is a powerful tool for observing the evolution of transient structures at the atomic level. However, temporal resolution is a huge challenge for UEDs, mainly depending on the pulse duration. Unfortunately, the Coulomb force between electrons causes the pulse duration to increase continually when propagating, reducing the temporal resolution. In this paper, we theoretically design a radio frequency (RF) compression cavity using the finite-element method of electromagnetic\u2013thermal coupling to overcome this limitation and obtain a high-brightness, short-pulse-duration, and stable electron beam. In addition, the cavity\u2019s size parameters are optimized, and a water-cooling system is designed to ensure stable operation. To the best of our knowledge, this is the first time that the electromagnetic\u2013thermal coupling method has been used to study the RF cavity applied to UED. The results show that the RF cavity operates in TM010 mode with a resonant frequency of 2970 MHz and generates a resonant electric field. This mode of operation generates an electric field that varies periodically and transiently, compressing the electronic pulse duration. The electromagnetic\u2013thermal coupling method proposed in this study effectively improves the temporal resolution of UED.<\/jats:p>","DOI":"10.3390\/s23177455","type":"journal-article","created":{"date-parts":[[2023,8,28]],"date-time":"2023-08-28T06:10:22Z","timestamp":1693203022000},"page":"7455","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Electromagnetic-Thermal Coupling Study for RF Compression Cavity Applied to Ultrafast Electron Diffraction"],"prefix":"10.3390","volume":"23","author":[{"given":"Zhen","family":"Wang","sequence":"first","affiliation":[{"name":"The Institute of Technological Sciences, Wuhan University, Wuhan 430072, China"}]},{"given":"Jian","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Electrical & Electronic Engineering, Wuhan Polytechnic University, Wuhan 430023, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4049-2180","authenticated-orcid":false,"given":"Xintian","family":"Cai","sequence":"additional","affiliation":[{"name":"The Institute of Technological Sciences, Wuhan University, Wuhan 430072, China"}]},{"given":"Zhiyin","family":"Gan","sequence":"additional","affiliation":[{"name":"School of Mechanical Science & Engineering, Huazhong University of Science & Technology, Wuhan 430074, China"}]},{"given":"Caoyue","family":"Ji","sequence":"additional","affiliation":[{"name":"The Institute of Technological Sciences, Wuhan University, Wuhan 430072, China"}]},{"given":"Cheng","family":"Lei","sequence":"additional","affiliation":[{"name":"The Institute of Technological Sciences, Wuhan University, Wuhan 430072, China"}]},{"given":"Sheng","family":"Liu","sequence":"additional","affiliation":[{"name":"The Institute of Technological Sciences, Wuhan University, Wuhan 430072, China"},{"name":"School of Power & Mechanical Engineering, Wuhan University, Wuhan 430072, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"045004","DOI":"10.1103\/RevModPhys.94.045004","article-title":"Ultrafast electron diffraction: Visualizing dynamic states of matter","volume":"94","author":"Filippetto","year":"2022","journal-title":"Rev. Mod. Phys."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1038\/s41566-020-0613-1","article-title":"Ultrashort electron probe opportunities","volume":"14","author":"Musumeci","year":"2020","journal-title":"Nat. Photonics"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"618","DOI":"10.1038\/s41563-020-00865-5","article-title":"Visualization of dynamic polaronic strain fields in hybrid lead halide perovskites","volume":"20","author":"Guzelturk","year":"2021","journal-title":"Nat. Mater."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1126\/science.aaa0217","article-title":"Four-dimensional imaging of carrier interface dynamics in p-n junctions","volume":"347","author":"Najafi","year":"2015","journal-title":"Science"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"4430","DOI":"10.1038\/s41467-020-18121-4","article-title":"Extended anharmonic collapse of phonon dispersions in SnS and SnSe","volume":"11","author":"Yang","year":"2020","journal-title":"Nat. Commun."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"100302","DOI":"10.1103\/PhysRevB.101.100302","article-title":"Tracking the ultrafast nonequilibrium energy flow between electronic and lattice degrees of freedom in crystalline nickel","volume":"101","author":"Maldonado","year":"2020","journal-title":"Phys. Rev. B"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1073\/pnas.1522869113","article-title":"On the dynamical nature of the active center in a single-site photocatalyst visualized by 4D ultrafast electron microscopy","volume":"113","author":"Yoo","year":"2016","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"214115","DOI":"10.1103\/PhysRevB.100.214115","article-title":"Time- and momentum-resolved phonon population dynamics with ul-trafast electron diffuse scattering","volume":"100","author":"Stern","year":"2019","journal-title":"Phys. Rev. B"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1038\/s42005-021-00650-z","article-title":"Ultrafast optical melting of trimer superstructure in layered 1T\u2032-TaTe2","volume":"4","author":"Siddiqui","year":"2021","journal-title":"Commun. Phys."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"eabf2810","DOI":"10.1126\/sciadv.abf2810","article-title":"Mechanisms of electron-phonon coupling unraveled in momentum and time: The case of soft phonons in TiSe2","volume":"7","author":"Otto","year":"2021","journal-title":"Sci. Adv."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"10976","DOI":"10.1073\/pnas.1309690110","article-title":"Exceptional rigidity and biomechanics of amyloid revealed by 4D electron mi-croscopy","volume":"110","author":"Fitzpatrick","year":"2013","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"081901","DOI":"10.1063\/1.4747155","article-title":"Ultrafast electron diffraction with radio-frequency compressed electron pulses","volume":"101","author":"Chatelain","year":"2012","journal-title":"Appl. Phys. Lett."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"11066","DOI":"10.1021\/acs.chemrev.6b00770","article-title":"Capturing Chemistry in Action with Electrons: Realization of Atomically Resolved Reaction Dynamics","volume":"117","author":"Ischenko","year":"2017","journal-title":"Chem. Rev."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"155504","DOI":"10.1103\/PhysRevLett.100.155504","article-title":"Electronically Driven Structure Changes of Si Captured by Femtosecond Electron Diffraction","volume":"100","author":"Harb","year":"2008","journal-title":"Phys. Rev. Lett."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1016\/j.chemphys.2003.11.040","article-title":"Femtosecond electron diffraction studies of strongly driven structural phase tran-sitions","volume":"299","author":"Siwick","year":"2004","journal-title":"Chem. Phys."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1382","DOI":"10.1126\/science.1090052","article-title":"An Atomic-Level View of Melting Using Femtosecond Electron Diffraction","volume":"302","author":"Siwick","year":"2003","journal-title":"Science"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"013109","DOI":"10.1063\/1.4905335","article-title":"A compact electron gun for time-resolved electron diffraction","volume":"86","author":"Robinson","year":"2015","journal-title":"Rev. Sci. Instrum."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"044903","DOI":"10.1063\/1.4906786","article-title":"Compact femtosecond electron diffractometer with 100 keV electron bunches approaching the single-electron pulse duration limit","volume":"117","author":"Waldecker","year":"2014","journal-title":"J. Appl. Phys."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1016\/j.nima.2013.12.031","article-title":"Generation of sub-fs electron beams at few-MeV energies","volume":"740","author":"Floettmann","year":"2014","journal-title":"Nucl. Instrum. Methods Phys. Res. Sect. A Accel. Spectrom. Detect. Assoc. Equip."},{"key":"ref_20","first-page":"390","article-title":"Potential of Femtosecond Electron Diffraction Using Near-Relativistic Electrons from a Photocathode RF Electron Gun","volume":"48","author":"Wang","year":"2006","journal-title":"J. Korean Phys. Soc."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1126\/science.aae0003","article-title":"All-optical control and metrology of electron pulses","volume":"352","author":"Kealhofer","year":"2016","journal-title":"Science"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"021303","DOI":"10.1103\/PhysRevAccelBeams.19.021303","article-title":"Direct longitudinal laser acceleration of electrons in free space","volume":"19","author":"Carbajo","year":"2016","journal-title":"Phys. Rev. Accel. Beams"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"063004","DOI":"10.1088\/1367-2630\/17\/6\/063004","article-title":"Femtosecond time-resolved MeV electron diffraction","volume":"17","author":"Zhu","year":"2015","journal-title":"New J. Phys."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1016\/j.chemphys.2009.07.013","article-title":"4D attosecond imaging with free electrons: Diffraction methods and potential applications","volume":"366","author":"Baum","year":"2009","journal-title":"Chem. Phys."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"093501","DOI":"10.1063\/1.2801027","article-title":"Electron source concept for single-shot sub-100 fs electron diffraction in the 100 keV range","volume":"102","author":"Root","year":"2007","journal-title":"J. Appl. Phys."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"264801","DOI":"10.1103\/PhysRevLett.105.264801","article-title":"Compression of Subrelativistic Space-Charge-Dominated Electron Bunches for Single-Shot Femtosecond Electron Diffraction","volume":"105","author":"Pasmans","year":"2010","journal-title":"Phys. Rev. Lett."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"272","DOI":"10.1088\/1367-2630\/8\/11\/272","article-title":"Sub-fs electron pulses for ultrafast electron diffraction","volume":"8","author":"Fill","year":"2006","journal-title":"New J. Phys."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"073055","DOI":"10.1088\/1367-2630\/14\/7\/073055","article-title":"Compression of single-electron pulses with a microwave cavity","volume":"14","author":"Gliserin","year":"2012","journal-title":"New J. Phys."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"215004","DOI":"10.1103\/PhysRevLett.105.215004","article-title":"Single-Shot Femtosecond Electron Diffraction with Laser-Accelerated Electrons: Ex-perimental Demonstration of Electron Pulse Compression","volume":"105","author":"Tokita","year":"2010","journal-title":"Phys. Rev. Lett."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1643","DOI":"10.1063\/1.1487437","article-title":"Ultrafast electron optics: Propagation dynamics of femtosecond electron packets","volume":"92","author":"Siwick","year":"2002","journal-title":"J. Appl. Phys."},{"unstructured":"Pulsar Physics (2023, July 05). General Particle Tracer. Available online: www.pulsar.nl\/gpt.","key":"ref_31"},{"unstructured":"van Oudheusden, T. (2010). Electron Source for Sub-Relativistic Single-Shot Femtosecond Diffraction. [Ph.D. Thesis, Technische Universiteit Eindhoven].","key":"ref_32"},{"doi-asserted-by":"crossref","unstructured":"Wangler, T.P. (2008). RF Linear Accelerators, John Wiley.","key":"ref_33","DOI":"10.1002\/9783527623426"},{"unstructured":"Los Alamos National Lab. (LANL) (1987). Reference manual for the Poisson\/Superfish Group of Codes, Los Alamos National Lab. (LANL).","key":"ref_34"},{"unstructured":"Incropera, F.P., and Dewitt, D.P. (1996). Fundamental of Heat and Mass Transfer, John Wiley & Sons.","key":"ref_35"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/17\/7455\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:40:17Z","timestamp":1760128817000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/17\/7455"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,8,27]]},"references-count":35,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2023,9]]}},"alternative-id":["s23177455"],"URL":"https:\/\/doi.org\/10.3390\/s23177455","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2023,8,27]]}}}