Charging of Ge/Si Dots

ORAL

Abstract

We have modeled the charging of Ge/Si dots with path integrals for comparison with C-V experiments. The experimental samples have small Ge huts or larger Ge-Si domes embedded~in n-doped Si. By applying a negative gate voltage and measuring capacitance, we can count the number of electrons that sit on the quantum dots. In our theoretical analysis, we model the system as thermal equilibrium between electrons bound to the dots and electrons in the bulk, doped Si. Since the electrons sit in quantized energy states on the dots, we model the thermodynamics with a Feynman path integral. The electrons feel an attractive potential from the strained Si and below the dot, which we have modeled with atomistic strain calculations and an effective mass model. Using Monte~Carlo sampling, we can directly sample the charge density for different temperatures, doping densities, and dot structures; allowing us to count the number of electrons on the dot and compare directly to experiments.

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Authors

  • Sourabh Sinha

    Arizona State University

  • Seth Putterman

    Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA, Department of Physics, Arizona State University, Tempe, AZ 85287, USA, College of Optical Sciences, University of Arizona, Colorado State University, University of Virginia, Auburn University, Northern Kentucky University, Utah Valley State College, Brigham Young University, Arizona State University, University of Amsterdam, New Mexico State university, University of Minesota, Pulse Field Facility, NHMFL, LANL, NM, Institute of Physics ASCR , Czech Republic, University of Minesota-Twin City, New Mexico State University, Director, Advanced Photon Source, Argonne National Lab, Australian Synchotron Source, Advanced Photon Source, Argonne National Lab, University of Arizona, U.S. Naval Research Laboratory, Wellesley College, Observatoire de Paris, France, Freie Universitat Berlin, Florida State Univ., Univ. Sci. Tech. China, Iowa State University, Lawrence Livermore National Laboratory, Mahabad Azad University, Carnegie Mellon University, Tempe Preparatory Academy, University of California, Los Angeles

  • Seth Putterman

    Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA, Department of Physics, Arizona State University, Tempe, AZ 85287, USA, College of Optical Sciences, University of Arizona, Colorado State University, University of Virginia, Auburn University, Northern Kentucky University, Utah Valley State College, Brigham Young University, Arizona State University, University of Amsterdam, New Mexico State university, University of Minesota, Pulse Field Facility, NHMFL, LANL, NM, Institute of Physics ASCR , Czech Republic, University of Minesota-Twin City, New Mexico State University, Director, Advanced Photon Source, Argonne National Lab, Australian Synchotron Source, Advanced Photon Source, Argonne National Lab, University of Arizona, U.S. Naval Research Laboratory, Wellesley College, Observatoire de Paris, France, Freie Universitat Berlin, Florida State Univ., Univ. Sci. Tech. China, Iowa State University, Lawrence Livermore National Laboratory, Mahabad Azad University, Carnegie Mellon University, Tempe Preparatory Academy, University of California, Los Angeles

  • Seth Putterman

    Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA, Department of Physics, Arizona State University, Tempe, AZ 85287, USA, College of Optical Sciences, University of Arizona, Colorado State University, University of Virginia, Auburn University, Northern Kentucky University, Utah Valley State College, Brigham Young University, Arizona State University, University of Amsterdam, New Mexico State university, University of Minesota, Pulse Field Facility, NHMFL, LANL, NM, Institute of Physics ASCR , Czech Republic, University of Minesota-Twin City, New Mexico State University, Director, Advanced Photon Source, Argonne National Lab, Australian Synchotron Source, Advanced Photon Source, Argonne National Lab, University of Arizona, U.S. Naval Research Laboratory, Wellesley College, Observatoire de Paris, France, Freie Universitat Berlin, Florida State Univ., Univ. Sci. Tech. China, Iowa State University, Lawrence Livermore National Laboratory, Mahabad Azad University, Carnegie Mellon University, Tempe Preparatory Academy, University of California, Los Angeles