Eur. Phys. J. Appl. Phys. 35, 29–36 (2006) DOI: 10.1051/epjap:2006073 THE EUROPEAN PHYSICAL JOURNAL APPLIED PHYSICS Scanning probe microscopy, luminescence and third harmonic generation studies of elongated CdS:Mn nanostructures developed by energetic oxygen-ion-impact D. Mohanta 1, a , G.A. Ahmed 1 , A. Choudhury 1 , F. Singh 2 , D.K. Avasthi 2 , G. Boyer 3 , and G.A. Stanciu 4 1 Department of Physics, Tezpur University, PO Napaam, Assam – 784 028, India 2 Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi – 110 067, India 3 Laboratoire d’Optique Appliqu´ee, ENSTA - ´ Ecole polytechnique, Centre de l’Yvette, 91128 Palaiseau Cedex, France 4 University “Politehnica” of Bucharest, 313 Splaiul Independentei str., sector 6, 060032 Bucharest, Romania Received: 3 November 2005 / Received in final form: 3 May 2006 / Accepted: 4 May 2006 Published online: 6 July 2006 – c  EDP Sciences Abstract. Manganese-doped cadmium sulfide nanoparticles are synthesized in a flexible polymer matrix (synthetic rubber) by a chemical route. They are bombarded with 80-MeV oxygen ions having electronic energy loss (Se) dominant over nuclear energy loss (Sn) and with fluence variation 10 11 –10 13 ions/cm 2 . Piling up of nanoparticles along certain direction was observed in atomic force microscopy (AFM) images of irradiated samples. Such elongated nanostructures are as a result of nanoparticle growth during ion passage through the samples. Specifically, elongated structures in the form of nanoneedles, nanochannels and nanorods have been observed. The fluence dependent photoluminescence spectra (PL) show significant luminescent peaks at 445 nm and 706 nm, respectively which are tunable with ion fluence. Such a tunability could be promising as lasing materials in nano-luminescent devices and laser diodes. Further, detection of efficient third harmonic generation (THG) in these samples (by using irradiation of a Cr:fosterite laser) could be promising in nanoscopy and nonlinear optics. PACS. 82.35.Np Nanoparticles in polymers – 81.40.Wx Radiation treatment (particle and electromag- netic) – 82.35.Ej Nonlinear optics with polymers – 87.64.Tt Confocal microscopy – 42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation 1 Introduction Low dimensional elongated semiconductor nanostructures such as nanotubes, nanorods, nanoneedles etc. have re- ceived considerable interest for their potential use in the vast arena of nanoelectronics and nanoscopy. This is be- cause of their typical size, morphology and electronic prop- erties. Normally, such 1D structures allow carrier move- ment along certain direction with restricted motion along rest two dimensions. Contrary to bulk density of states (DOS), such a system displays definite change over to dis- crete energy states. Previously, several approaches have been taken to synthesize nanowires/nanorods of metals, semiconductors or inorganic compounds. Earlier work in this field include filling of carbon nanotubes [1,2] with metals or metal oxides in the molten state, 1D nanochan- nels in porous anodic alumina [3] etc. Very recently, production of nanorod, nanowire and nanoneedle like structures mostly in oxide, sulfide or nitride compounds of direct band gap semiconductor systems have been stud- ied by different workers [4–8]. However, thermal evapora- a e-mail: best@tezu.ernet.in tion of powders under a gas flow followed by deposition on a substrate has been reported as an obvious method to obtain nanowires, nanorods, or nanotubes of different semiconductors. The growth takes place either by catalyst- assisted technique [9] or by a vapor-solid process [10]. Also, attempt has been made to fabricate transition-metal oxide nanorods by inexpensive sol-gel process [11]. Energetic ion irradiation studies initially started with a motive to detect energetic particles followed by under- standing ion-matter interaction. However, now it has been more useful to alter materials. It is known that an ener- getic ion beam loses its energy via elastic collision with the nuclei of the material (nuclear energy loss) and inelas- tic collision with the surrounding electronic clouds (elec- tronic energy loss). Normally, S e >S n for MeV energy scale and S n >S e for KeV energy scale. The former case is relevant for columnar defect formation due to material amorphization along ion track. Etching out of these de- fects in polymers provides a system for template synthesis of nanostructures [12,13] whereas later one is useful for producing size controlled self-assembled nanostructures by way of ion implantation and ion beam mixing [14–17]. Article published by EDP Sciences and available at http://www.edpsciences.org/epjap or http://dx.doi.org/10.1051/epjap:2006073