Circularly polarized luminescence microscopy for the imaging of charge and spin diffusion in semiconductors

Favorskiy, I.; Vu, D.; Peytavit, E.; Arscott, S.; Paget, D.; Rowe, A. C. H.
October 2010
Review of Scientific Instruments;Oct2010, Vol. 81 Issue 10, p103902
Academic Journal
Room temperature electronic diffusion is studied in 3 μm thick epitaxial p+ GaAs lift-off films using a novel circularly polarized photoluminescence microscope. The method is equivalent to using a standard optical microscope and provides a contactless means to measure both the charge (L) and spin (Ls) diffusion lengths simultaneously. The measured values of L and Ls are in excellent agreement with the spatially averaged polarization and a sharp reduction in these two quantities (L from 21.3 to 1.2 μm and Ls from 1.3 to 0.8 μm) is found with increasing surface recombination velocity. Outward diffusion results in a factor of 10 increase in the polarization at the excitation spot. The range of materials to which the technique can be applied, as well as a comparison with other existing methods for the measurement of spin diffusion, is discussed.


Related Articles

  • Observation of long-range exciton diffusion in highly ordered organic semiconductors. Najafov, H.; Lee, B.; Zhou, Q.; Feldman, L. C.; Podzorov, V. // Nature Materials;Nov2010, Vol. 9 Issue 11, p938 

    Excitons in polycrystalline and disordered films of organic semiconductors have been shown to diffuse over distances of 10-50 nm. Here, using polarization- and wavelength-dependent photoconductivity in the highly ordered organic semiconductor rubrene, we show that the diffusion of triplet...

  • Transition from the strong- to the weak-coupling regime in semiconductor microcavities: Polarization dependence. Ballarini, D.; Amo, A.; Viña, L.; Sanvitto, D.; Skolnick, M. S.; Roberts, J. S. // Applied Physics Letters;5/14/2007, Vol. 90 Issue 20, p201905 

    The dependence on the polariton spin orientation of the transition from the strong- to the weak-coupling regime in InGaAs semiconductor microcavities is experimentally studied by means of time-resolved photoluminescence. Polaritons are nonresonantly excited by circularly polarized pulses and the...

  • Polarization-sensitive optical phenomena in thick semiconducting nanowires. Ruda, H. E.; Shik, A. // Journal of Applied Physics;7/15/2006, Vol. 100 Issue 2, p024314 

    For semiconducting nanowires with the dielectric constant [variant_greek_epsilon] differing from that of their environment, the distribution of ac electric fields, created in a nanowire by an external lightwave and emitted outside by an effective dipole in a nanowire, is found. The results are...

  • Polarization reversal in LiNbO[sub 3] crystals under asymmetric diffusion conditions. Kugel, V.D.; Rosenman, G. // Applied Physics Letters;11/7/1994, Vol. 65 Issue 19, p2398 

    Describes the polarization reversal in LiNbO[sub 3] crystals under asymmetric diffusion conditions. Implication of the limitation of outdiffusion from -C surface; Effects of consequent indiffusion on the bidomain structure and inverted layer depth; Explanation of the phenomenon in terms of the...

  • Forced polarization of α-sapphire induced by coated LiNbO3 and LiTaO3 films. Yang, X.; Wu, X. L.; Feng, Y.; Li, J.; Jiang, M. // Applied Physics Letters;4/5/2004, Vol. 84 Issue 14, p2623 

    We have investigated the formation mechanism of the interfacial electric field in LiNbO3(or LiTaO3)/α-sapphire crystal structures, which is important in understanding the photoluminescence properties of this kind of ferroelectric film-coated crystal material. It is revealed that the...

  • Luminescence properties and optical dephasing in a glass-ceramic containing sodium-niobate nanocrystals. Almeida, E.; Menezes, L. de S.; de Araújo, Cid B.; Lipovskii, A. A. // Journal of Applied Physics;Jun2011, Vol. 109 Issue 11, p113108 

    Photoluminescence (PL) and degenerate four-wave-mixing (DFWM) experiments were performed in a silica-niobic composite containing NaNbO3 nanocrystals. The PL results indicate the presence of in-gap states attributed to excitons in the nanocrystals and defect centers. The luminescence of the...

  • Spectroscopic strain measurement methodology: Degree-of-polarization photoluminescence versus photocurrent spectroscopy. Tomm, Jens W.; Tran Quoc Tien; Cassidy, Daniel T. // Applied Physics Letters;3/27/2006, Vol. 88 Issue 13, p133504 

    A methodological approach to strain analysis in semiconductor devices is presented. Two methods, degree-of-polarization of photoluminescence and photocurrent spectroscopy, are compared by analyzing a spatially inhomogeneous strained test sample, namely, a high-power diode laser array that is...

  • Molecular Beam Epitaxial Growth and Characterization of Cd-Based II-VI Wide-Bandgap Compounds on Si Substrates. Brill, G.; Chen, Y.; Amirtharaj, P. M.; Sarney, W.; Chandler-Horowitz, D.; Dhar, N. K. // Journal of Electronic Materials;May2005, Vol. 34 Issue 5, p655 

    We have carried out a detailed study on the growth of Cd-based II-VI compounds on Si substrates using molecular beam epitaxy (MBE), CdTe, CdSe, CdSeTe, and CdZnSeTe layers were nucleated and grown on Si(211) substrates in order to study a broad range of semiconductor properties, such as crystal...

  • Improved visible photoluminescence from porous silicon with surface Si–Ag bonds. Sun, J.; Lu, Y. W.; Du, X. W.; Kulinich, S. A. // Applied Physics Letters;4/25/2005, Vol. 86 Issue 17, p171905 

    Porous silicon with surface Si–Ag bonds was prepared by a two-step method combining chemical etching and electrochemical anodization. The microstructure was analyzed by scanning electron microscopy, and the bond structure was evaluated by energy dispersion spectroscopy and Fourier...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics