title: Particle size-dependent giant nonlinear absorption in nanostructured Ni-Ti alloys.
abstract: The nonlinear absorption in nanostructured Ni-Ti alloys, fabricated by electrochemical deposition, was investigated at 532 and 1064 nm. The type of nonlinear absorption (saturable or reverse saturable absorption) was observed to depend on the laser intensity as well as on the nanoparticle size. The nanostructured Ni-Ti alloys comprising particle mean diameters of 20 and 30 nm exhibited large three-photon absorption (3PA coefficient approximately 10(6) cm(3)/GW(2)) and large two-photon absorption (2PA coefficient approximately 10(5) cm/GW) at 532 nm, respectively. The observed change over from reverse saturable absorption to saturable absorption at high peak intensities has qualitatively been analyzed by the excited-state theory of conduction electrons.
authors.affiliation: Division of Energy Systems Research, Ajou University, Suwon, Korea.
authors.forename: John Kiran
authors.initials: JK
authors.lastname: Anthony
authors.forename: Hee Cheoul
authors.initials: HC
authors.lastname: Kim
authors.forename: Hwang Woon
authors.initials: HW
authors.lastname: Lee
authors.forename: S Kumar
authors.initials: SK
authors.lastname: Mahapatra
authors.forename: Hae Min
authors.initials: HM
authors.lastname: Lee
authors.forename: Chang Koo
authors.initials: CK
authors.lastname: Kim
authors.forename: Kihong
authors.initials: K
authors.lastname: Kim
authors.forename: Hanjo
authors.initials: H
authors.lastname: Lim
authors.forename: Fabian
authors.initials: F
authors.lastname: Rotermund
mesh_terms: D000042:Absorption; D000497:Alloys; D003198:Computer Simulation; D004735:Energy Transfer; D008027:Light; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D009532:Nickel / Q000737:chemistry*; D017711:Nonlinear Dynamics; D010316:Particle Size; D012542:Scattering, Radiation; D014025:Titanium / Q000737:chemistry*
chemical_list: D000497:Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium