Moving towards nano-TCAD through multimillion atom quantum dot simulations matching experimental data

Abstract

Low-loss optical communication requires light sources at 1.5um wavelengths. Experiments showed without much theoretical guidance that InAs/GaAs quantum dots (QDs) may be tuned to such wavelengths by adjusting the In fraction in an InxGa1-xAs strain-reducing capping layer (SRCL). In this work systematic multimillion atom electronic structure calculations qualitatively and quantitatively explain for the first time available experimental data. The NEMO 3-D simulations treat strain in a 15 million atom system and electronic structure in a subset of ~9 million atoms using the experimentally given nominal geometries and without any further parameter adjustments the simulations match the nonlinear behavior of experimental data very closely. With the match to experimental data and the availability of internal model quantities significant insight can be gained through mapping to reduced order models and their relative importance. We can also demonstrate that starting from simple models has in the past led to the wrong conclusions. The critical new insight presented here is that the QD changes its shape. The quantitative simulation agreement with experiment without any material or geometry parameter adjustment in a general atomistic tool leads us to believe that the era of nano Technology Computer Aided Design (nano-TCAD) is approaching. NEMO 3-D will be released on nanoHUB.org where the community can duplicate and expand on the results presented here through interactive simulations.

14 pages, 11 figures. Accepted for Publication in IEEE Trans. on Nanotechnology

References in corpus (2)

• Valley splitting in strained silicon quantum wells
• High precision quantum control of single donor spins in silicon

Cited by in corpus (19)

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• Experimental and Atomistic Theoretical Study of Degree of Polarization from Multi-layer InAs/GaAs Quantum Dots
• Quantitative Excited State Spectroscopy of a Single InGaAs Quantum Dot Molecule through Multi-million Atom Electronic Structure Calculations
• Experimental and Theoretical Study of Polarization-dependent Optical Transitions from InAs Quantum Dots at Telecommunication-Wavelengths (1.3-1.5μm)
• Atomistic simulations of adiabatic coherent electron transport in triple donor systems
• Polarization Response in InAs Quantum Dots: Theoretical Correlation between Composition and Electronic Properties
• Multiscale Metrology and Optimization of Ultra-Scaled InAs Quantum Well FETs
• Impact of disorder on the optoelectronic properties of GaN${}_y$As${}_{1-x-y}$Bi${}_x$ alloys and heterostructures
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• Million Atom Electronic Structure and Device Calculations on Peta-Scale Computers
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• Understanding electric field control of electronic and optical properties of strongly-coupled multi-layer quantum dot molecules
• Tuning of polarisation sensitivity in closely-stacked trilayer InAs/GaAs quantum dots induced by overgrowth dynamics
• Towards low-loss telecom-wavelength photonic devices by designing GaBi${}_x$As${}_{1-x}$/GaAs core$-$shell nanowires
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• Nanowire design by deep learning for energy efficient photonic technologies
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