Applied Physics Letters

Population dynamics in epitaxial Er2O3 thin films grown on Si(111)

Takehiko Tawara, Hiroo Omi, T. Hozumi, R. Kaji, S. Adachi, Hideki Gotoh, Tetsuomi Sogawa

Published Jun 17, 2013• 22 citations

Abstract

We grow single crystal erbium-oxide (Er2O3) epitaxially on a Si (111) substrate by using molecular beam epitaxy and investigate the population dynamics in Er3+ ions for the coherent manipulation of the population in Er2O3. Sharp and discrete Stark energy levels of the 4I13/2 manifold as small as 200 μeV are observed with inhomogeneous broadening caused by the uniform crystal field of the epitaxial Er2O3. We also experimentally determine the time constant of the resonant population transfer between spatially distant Er3+-ion sites, which is limited to the manipulation time of the population in the Er2O3 crystals. Using selective excitation of the Stark level in the 4I13/2 manifold, we obtain the energy transfer times between spatially distant Er3+ ions, and they are about 2 μs between sites whose crystallographic symmetry is different and 10 μs between sites whose symmetry is the same.

DOI: 10.1063/1.4812294

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