Arturo Mendoza-Galván, Roger Magnusson, Nicklas Jansson, Hans Arwin, Kenneth Järrendahl
{"title":"用穆勒矩阵光谱椭偏仪分析镜花藻角质层中的双手性结构","authors":"Arturo Mendoza-Galván, Roger Magnusson, Nicklas Jansson, Hans Arwin, Kenneth Järrendahl","doi":"10.3389/fphy.2024.1444297","DOIUrl":null,"url":null,"abstract":"Many species of beetles from the family Scarabaeidae reflect light with near-circular polarization. In some cases, spectral narrow-band polarization phenomena result in a distinct color with a metallic shine. In other cases, broad-band features are seen, and these beetles have a silvery or goldish appearance. These features in the cuticles originate from helicoidal structures, so-called circular Bragg structures and also referred to as Bouligand structures. In this communication, <jats:italic>Protaetia mirifica,</jats:italic> exhibiting near-circular polarization properties in dual spectral regions, centered approximately at the wavelengths of 474 and 770 nm, is investigated in considerable detail using Mueller matrix spectroscopic ellipsometry (MMSE). From interference oscillations in the MMSE spectra, the pitch profile of the helicoidal structures in the beetle cuticle is extracted and further used in electromagnetic modeling of the cuticle structure, including the determination of epicuticle and exocuticle thicknesses (280 nm and 8.1 <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mrow><mml:mi>μ</mml:mi><mml:mi mathvariant=\"normal\">m</mml:mi></mml:mrow></mml:math></jats:inline-formula>, respectively) and anisotropic optical properties. These findings are confirmed by scanning electron microscopy. The analysis shows that the uppermost <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mrow><mml:mn>4</mml:mn><mml:mtext> </mml:mtext><mml:mi>μ</mml:mi><mml:mi mathvariant=\"normal\">m</mml:mi></mml:mrow></mml:math></jats:inline-formula> of the cuticle has a nearly constant pitch of 310 nm, which abruptly jumps to 440 nm and then gradually increases up to 575 nm. Sum decompositions of MMSE spectra reveal that the beetle cuticle reflects like a circular polarizer or like a dielectric mirror, depending on the spectral region.","PeriodicalId":12507,"journal":{"name":"Frontiers in Physics","volume":"62 1","pages":""},"PeriodicalIF":1.9000,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Dual chiral structures in the cuticle of Protaetia mirifica analyzed with Mueller matrix spectroscopic ellipsometry\",\"authors\":\"Arturo Mendoza-Galván, Roger Magnusson, Nicklas Jansson, Hans Arwin, Kenneth Järrendahl\",\"doi\":\"10.3389/fphy.2024.1444297\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Many species of beetles from the family Scarabaeidae reflect light with near-circular polarization. In some cases, spectral narrow-band polarization phenomena result in a distinct color with a metallic shine. In other cases, broad-band features are seen, and these beetles have a silvery or goldish appearance. These features in the cuticles originate from helicoidal structures, so-called circular Bragg structures and also referred to as Bouligand structures. In this communication, <jats:italic>Protaetia mirifica,</jats:italic> exhibiting near-circular polarization properties in dual spectral regions, centered approximately at the wavelengths of 474 and 770 nm, is investigated in considerable detail using Mueller matrix spectroscopic ellipsometry (MMSE). From interference oscillations in the MMSE spectra, the pitch profile of the helicoidal structures in the beetle cuticle is extracted and further used in electromagnetic modeling of the cuticle structure, including the determination of epicuticle and exocuticle thicknesses (280 nm and 8.1 <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mrow><mml:mi>μ</mml:mi><mml:mi mathvariant=\\\"normal\\\">m</mml:mi></mml:mrow></mml:math></jats:inline-formula>, respectively) and anisotropic optical properties. These findings are confirmed by scanning electron microscopy. The analysis shows that the uppermost <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mrow><mml:mn>4</mml:mn><mml:mtext> </mml:mtext><mml:mi>μ</mml:mi><mml:mi mathvariant=\\\"normal\\\">m</mml:mi></mml:mrow></mml:math></jats:inline-formula> of the cuticle has a nearly constant pitch of 310 nm, which abruptly jumps to 440 nm and then gradually increases up to 575 nm. Sum decompositions of MMSE spectra reveal that the beetle cuticle reflects like a circular polarizer or like a dielectric mirror, depending on the spectral region.\",\"PeriodicalId\":12507,\"journal\":{\"name\":\"Frontiers in Physics\",\"volume\":\"62 1\",\"pages\":\"\"},\"PeriodicalIF\":1.9000,\"publicationDate\":\"2024-07-25\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Frontiers in Physics\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.3389/fphy.2024.1444297\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"PHYSICS, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Frontiers in Physics","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.3389/fphy.2024.1444297","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
Dual chiral structures in the cuticle of Protaetia mirifica analyzed with Mueller matrix spectroscopic ellipsometry
Many species of beetles from the family Scarabaeidae reflect light with near-circular polarization. In some cases, spectral narrow-band polarization phenomena result in a distinct color with a metallic shine. In other cases, broad-band features are seen, and these beetles have a silvery or goldish appearance. These features in the cuticles originate from helicoidal structures, so-called circular Bragg structures and also referred to as Bouligand structures. In this communication, Protaetia mirifica, exhibiting near-circular polarization properties in dual spectral regions, centered approximately at the wavelengths of 474 and 770 nm, is investigated in considerable detail using Mueller matrix spectroscopic ellipsometry (MMSE). From interference oscillations in the MMSE spectra, the pitch profile of the helicoidal structures in the beetle cuticle is extracted and further used in electromagnetic modeling of the cuticle structure, including the determination of epicuticle and exocuticle thicknesses (280 nm and 8.1 μm, respectively) and anisotropic optical properties. These findings are confirmed by scanning electron microscopy. The analysis shows that the uppermost 4μm of the cuticle has a nearly constant pitch of 310 nm, which abruptly jumps to 440 nm and then gradually increases up to 575 nm. Sum decompositions of MMSE spectra reveal that the beetle cuticle reflects like a circular polarizer or like a dielectric mirror, depending on the spectral region.
期刊介绍:
Frontiers in Physics publishes rigorously peer-reviewed research across the entire field, from experimental, to computational and theoretical physics. This multidisciplinary open-access journal is at the forefront of disseminating and communicating scientific knowledge and impactful discoveries to researchers, academics, engineers and the public worldwide.