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OPTICAL LIMITING PROPERTIES OF DETONATION NANODIAMOND. SUSPENSIONS. Viatcheslav Vanyukov. 1,2. , Tatyana Mogileva. 2. , Gennady Mikheev. 2.
OPTICAL LIMITING PROPERTIES OF DETONATION NANODIAMOND SUSPENSIONS Viatcheslav Vanyukov1,2, Tatyana Mogileva2, Gennady Mikheev2, Alexey Puzyr3, Vladimir Bondar3, Yuri Svirko1 1

Department of Physics and Mathematics, University of Eastern Finland, Joensuu 80101, Finland 2 Institute of Mechanics, Russian Academy of Sciences, Izhevsk 426067, Russia 3 Institute of Biophysics, Russian Academy of Sciences, Krasnoyarsk 660036, Russia [email protected] Optical limiting (OL) is one of the interesting phenomena in the interaction of the intense laser pulses with condensed matter. In the experiment, OL manifests itself as a reduction of the transmittance when the input fluence increases [1], being of interest for development of devices capable to protect sensitive optical components or human eye from laser radiation [2]. We report on the limiting properties of stable aqueous suspensions of detonation ND clusters with average size of 110 nm. In the experiment, we employed TEM00 mode (M2=1) of a single-frequency Nd3+: YAG laser with pulse duration of 17 ns and a repetition rate of 1 Нz. The OL in ND suspensions were investigated by both closed and open-aperture Z – scan techniques [3].

Fig. 1. The normalized transmittance for closed (a) and open-aperture (b) Z-scan and energy of scattered pulses (c) as a function of sample position z.

Figure 1 presents the results of Z-scan measurements with the energy of 30 µJ. One can observe from Fig. 1(a) that in the closed-aperture Z – scan the normalized transmittance at |z| < 20 mm remain an even function of the coordinate z indicating that the nonlinear refraction is negligible. It can be seen from Figs. 1(b) and 1(c) that although transmittances dip at z = 0 does not exceed 25%, the peak of the nonlinear scattering is also observed indicating that OL originates from the nonlinear scattering.

In conclusion, we observed the optical limiting of nanosecond laser pulses at 532 nm in stable suspension of detonation nanodiamonds. The OL originates from the nonlinear absorption and the nonlinear scattering rather than from the nonlinear refraction. The suspensions showed high ray stability and can be employed for optical limiting of intense light beams. [1] L. W. Tutt, T. F. Bogges, Prog. Quant. Electronics 17, 299 (1993). [2] L. W. Tutt, A. Kost, Nature, 356, 6366 (1992). [3] E. Van Stryland, S.-B. Mansoor, Characterization Techniques and Tabulations for Organic Nonlinear Materials, (Marcel Dekker, 1998).