Spherical gallium nanodroplets

Trabajo presentado en el 21st European Workshop on Molecular Beam Epitaxy (EuroMBE 2023), celebrado en Madrid (España), del 16 al 19 de abril de 2023Gallium (Ga) nanoparticles has unique characteristics that could enable new devices based on phase changes, such as optical switches and memories and active plasmonic platforms [1]. Gallium is also a very interesting material for its biocompatibility properties and many other applications [2]. We show the fabrication by MBE of gallium nanodroplets on GaAs(001) by droplet epitaxy [3, 4]. Furthermore, it is possible to control the shape of the nanodroplets by changing the wettability of Ga over the surface by evaporation of one monolayer of carbon [3] prior to the droplet formation. This effect is used for obtaining almost perfectly spherical Ga nanodroplets on GaAs and could be used in many other substrates. We acknowledge the following projects: MAT2015-67021-R, S2018/NMT-4291 TEC2SPACE, CSIC13- 4E-1794, RTI2018-096937-B-C22, PID2021-124193OB-C22 and P2018/EMT-4308. References [1] Maria Losurdo, et al., ¿Thermally stable coexistence of liquid and solid phases in gallium nanoparticles¿, Nature Mat., Vol. 15, pp. 995-1002, 2016. [2] Michael D. Dickey, ¿Liquid metals at room temperature¿, Physics Today Vol. 74, 4, pp. 30- 36, 2021. [3] D. Fuster et al., ¿Optimization of a carbon evaporator cell for MBE growth¿, Vacuum, Vol. 181, pp. 109653(1)-109653(8), 2020. [4] D. Fuster, et al., ¿Fundamental role of arsenic flux in nanohole formation by Ga droplet etching on GaAs (001),¿ Nanoscale Res Lett. Vol. 9, pp. 309(1)-309(6), 2014.Service from the MiNa Laboratory at IMN (funding from CM), X-SEM Laboratory and funding projects MAT2015-67021-R, S2018/NMT-4291, TEC2SPACE, CSIC13-4E-1794, RTI2018-096937-B-C22, PID2021-124193OB-C22 and P2018/EMT-430