Lighting up micro-structured materials with four-wave mixing microscopy

Surface‐enhanced micro‐CARS mapping of a nanostructured cerium dioxide/aluminum film surface with gold nanoparticle‐bound organic molecules

“…Hence, they can be expected to demonstrate surface‐enhanced CARS (SECARS) activity. After the first experimental observations and theoretical description, SECARS‐spectroscopy in recent times generates more and more research activities that are shortly summarized in the review papers . These activities, among others, are devoted to studying of peculiarities of SECARS itself, to biomedical applications, to finding the ways to reach a single‐molecule sensitivity, which with SECARS may be achievable for a much broader variety of substances than with classical SERS, due to potentially higher field enhancing factors, and even to investigations of arising possibility to engineer SERS‐active structures delivering the highest gain in the SECARS configuration .…”

“…After the first experimental observations [3][4][5] and theoretical description, [6] SECARS-spectroscopy in recent times generates more and more research activities that are shortly summarized in the review papers. [7][8][9] These activities, among others, are devoted to studying of peculiarities of SECARS itself, [10][11][12][13] to biomedical applications, [14][15][16][17] to finding the ways to reach a single-molecule sensitivity, [15,18,19] which with SECARS may be achievable for a much broader variety of substances than with classical SERS, due to potentially higher field enhancing factors, [9,11] and even to investigations of arising possibility to engineer SERS-active structures delivering the highest gain in the SECARS configuration. [20][21][22] But the field of the most interesting SECARS applications opens when the capability of the technique to be employed in femto-and picosecond time-resolved experiments is realized.…”

Laser intensity limits in surface‐enhanced linear and nonlinear Raman micro‐spectroscopy of organic molecule/Au‐nanoparticle conjugates

“…The slope of these dependences is~(0.1-0.2) × 10 −3 counts/μW 3 and rather corresponds to the level of Raman nonresonant signals defined in the study of Fabelinsky et al [39] as~4 × 10 −3 counts/μW 3 . These signals result, presumably, from two-color four-wave mixing processes near one-or two-photon absorption resonances [10,12,14,[42][43][44][45] within various unmodified Au NP structures immobilized on the CeO 2 film surface. The initial steep slope of the P aS versus (P p 2 × P S ) dependences in the bright spots is evaluated to be ≈0.003 counts/μW 3 .…”

“…The number of papers is constantly growing, and the achievements, frontiers, problems, and shortages are summarized in a number of recently published books and review articles. [1][2][3][4][5][6][7][8][9][10][11][12] Presently, the investigations are devoted, among other topics, to clarification of physical mechanisms of laser light interaction with SERS-active surfaces [13][14][15] and, in particular, of surface-enhanced coherent anti-Stokes Raman scattering (SECARS), [16][17][18][19][20][21] as well as to possible applications of SERS in biology, biochemistry and medicine, [4,[6][7][8]11,[22][23][24][25] chemistry, [9,11,26] and pharmacy. [27] Special interest in recent years is the development of linear and nonlinear versions of SERS excited by femtosecond and picosecond laser sources.…”

“…Scientific research around surface‐enhanced Raman scattering (SERS)‐active surfaces is being conducted already for 45 years. The number of papers is constantly growing, and the achievements, frontiers, problems, and shortages are summarized in a number of recently published books and review articles . Presently, the investigations are devoted, among other topics, to clarification of physical mechanisms of laser light interaction with SERS‐active surfaces and, in particular, of surface‐enhanced coherent anti‐Stokes Raman scattering (SECARS), as well as to possible applications of SERS in biology, biochemistry and medicine, chemistry, and pharmacy .…”