Dr. Robert J. Walters Profile

Dr. Robert J. Walters

RETIRED at Packet Digital

SPIE Involvement:

Author

Publications (21)

SPIE Journal Paper | 31 December 2018 Open Access

Experimental demonstration of voltage-matched two-terminal tandem minimodules

Kirstin Alberi, James Moore, Kenneth Schmieder, Matthew Lumb, Robert Walters, Eric Armour, Leo Mathew, Rajesh Rao

JPE, Vol. 8, Issue 04, 045504, (December 2018) https://doi.org/10.1117/12.10.1117/1.JPE.8.045504

KEYWORDS: Silicon, Indium gallium phosphide, Monte Carlo methods, Solar cells, Solar energy, Resistance, Renewable energy, Tandem solar cells, Photovoltaics, Energy efficiency

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 14 March 2018 Presentation

The effect of excited state occupation and phonon broadening in the determination of the non-equilibrium hot-carrier temperature in InGaAsP quantum-well absorbers (Conference Presentation)

Hamidreza Esmaielpour, Vincent Whiteside, Louise Hirst, Joseph Tischler, Robert Walters, Ian Sellers

Proceedings Volume 10527, 1052706 (2018) https://doi.org/10.1117/12.2287446

KEYWORDS: Quantum wells, Phonons, Luminescence, Solar cells, Photovoltaics, Solar energy

Read Abstract +

SPIE Journal Paper | 1 November 2017

Simulated potential for enhanced performance of mechanically stacked hybrid III–V/Si tandem photovoltaic modules using DC–DC converters

Sara MacAlpine, David Bobela, Sarah Kurtz, Matthew Lumb, Kenneth Schmieder, James Moore, Robert Walters, Kirstin Alberi

JPE, Vol. 7, Issue 04, 042501, (November 2017) https://doi.org/10.1117/12.10.1117/1.JPE.7.042501

KEYWORDS: Silicon, Indium gallium phosphide, Photovoltaics, Solar cells, Crystals, Temperature metrology, Tandem solar cells, Solar energy, Systems modeling, Electronics

Read Abstract +

SPIE Journal Paper | 21 August 2017

Broken-gap quantum-well tunnel junctions grown on GaSb substrates

Matthew Lumb, Shawn Mack, Maria Gonzalez, Kenneth Schmieder, Mitchell F. Bennett, Chaffra Affouda, James Moore, Robert Walters

JPE, Vol. 7, Issue 03, 032501, (August 2017) https://doi.org/10.1117/12.10.1117/1.JPE.7.032501

KEYWORDS: Gallium antimonide, Quantum wells, Indium arsenide, Resistance, Silicon, Data modeling, Doping, Instrument modeling, Transparency, Antimony

Read Abstract +

Proceedings Article | 7 March 2014 Paper

Hot-carrier solar cell spectral insensitivity: Why develop the hot-carrier solar cell when we have multi-junction devices?

Louise Hirst, Matthew Lumb, Raymond Hoheisel, Simon Philipps, Andreas Bett, Robert Walters

Proceedings Volume 8981, 89810I (2014) https://doi.org/10.1117/12.2040698

KEYWORDS: Solar energy, Solar cells, Energy efficiency, Quantum wells, Photons, Sun, Photovoltaics, Indium gallium arsenide, Solids, Absorption

Read Abstract +

Proceedings Article | 7 March 2014 Paper

Modeling, design and experimental results for high efficiency multi-junction solar cells lattice matched to InP

María González, Matthew Lumb, Michael Yakes, Joshua Abell, Joseph Tischler, Christopher Bailey, Igor Vurgaftman, Jerry Meyer, Louise Hirst, Kenneth Schmieder, Sergio Molina, Francisco Delgado, Jessica G. Adams, Glen Hillier, Nicholas Ekins-Daukes, Robert Walters

Proceedings Volume 8981, 898117 (2014) https://doi.org/10.1117/12.2041289

KEYWORDS: Multijunction solar cells, Solar cells, Superlattices, Analytical research, Solar energy, Coastal modeling, Instrument modeling, Quantum wells, Indium gallium arsenide, Refractive index

Read Abstract +

Proceedings Article | 7 March 2014 Paper

Degradation modeling of InGaP/GaAs/Ge triple-junction solar cells irradiated by protons

S. Maximenko, M. Lumb, S. Messenger, R. Hoheisel, C. Affouda, D. Scheiman, M. Gonzalez, J. Lorentzen, P. Jenkins, R. Walters

Proceedings Volume 8981, 89810U (2014) https://doi.org/10.1117/12.2040938

KEYWORDS: Diffusion, Solar cells, Indium gallium phosphide, Gallium arsenide, External quantum efficiency, Quantum efficiency, Scanning electron microscopy, Line scan image sensors, Interfaces, Analytical research

Read Abstract +

Proceedings Article | 7 March 2014 Paper

The effects of electric field on InGaAs quantum well i-region placement in InAlGaAs solar cells

Christopher Bailey, Matthew Lumb, Raymond Hoheisel, Maria Gonzalez, David Forbes, Michael Yakes, Seth Hubbard, Louise Hirst, Justin Lorentzen, Joseph Tischler, Ken Schmieder, Cory Cress, Phillip Jenkins, Robert Walters

Proceedings Volume 8981, 898104 (2014) https://doi.org/10.1117/12.2041348

KEYWORDS: Quantum wells, Solar cells, Indium gallium arsenide, Doping, External quantum efficiency, Light emitting diodes, Absorption, Photovoltaics, Measurement devices, Interfaces

Read Abstract +

Proceedings Article | 7 March 2014 Paper

Analytical modeling of III-V solar cells close to the fundamental limit

Matthew Lumb, Myles Steiner, John Geisz, Robert Walters

Proceedings Volume 8981, 898114 (2014) https://doi.org/10.1117/12.2041359

KEYWORDS: Solar cells, Gallium arsenide, Data modeling, External quantum efficiency, Gold, Instrument modeling, Absorption, Reflectivity, Measurement devices, Indium gallium phosphide

Read Abstract +

SPIE Journal Paper | 11 September 2013 Open Access

Six not-so-easy pieces in intermediate band solar cell research

Antonio Marti Vega, Elisa Antolin, Pablo Linares, Iñigo Ramiro, Irene Artacho, Esther López, Estela Hernández, Alexander Mellor, Ignacio Tobías, David Marron, César Tablero, Ana Cristóbal, Christopher Bailey, Maria Gonzalez, Michael Yakes, Matthew Lumb, Robert Walters, Antonio Luque, Manuel Mendes

JPE, Vol. 3, Issue 01, 031299, (September 2013) https://doi.org/10.1117/12.10.1117/1.JPE.3.031299

KEYWORDS: Absorption, Electrons, Solar cells, Semiconductors, Gallium arsenide, Quantum dots, Electron holes, Solar energy, Manufacturing, N-type semiconductors

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 25 March 2013 Paper

Six not so easy pieces in intermediate band solar cell research

A. Martí, E. Antolín, P. García-Linares, I. Ramiro, I. Artacho, E. López, E. Hernández, M. Mendes, A. Mellor, I. Tobías, D. Fuertes Marrón, C. Tablero, A. Cristóbal, C. Bailey, M. Gonzalez, M. Yakes, M. Lumb, R. Walters, A. Luque

Proceedings Volume 8620, 86200J (2013) https://doi.org/10.1117/12.2002533

KEYWORDS: Absorption, Photons, Electrons, Solar cells, Quantum dots, Semiconductors, Electroluminescence, Solar energy, Gallium arsenide, Doping

Read Abstract +

Proceedings Article | 25 March 2013 Paper

Solar cell experiments for space: past, present and future

R. Hoheisel, S. Messenger, M. Lumb, M. Gonzalez, C. Bailey, D. Scheiman, S. Maximenko, P. Jenkins, R. Walters

Proceedings Volume 8620, 86200U (2013) https://doi.org/10.1117/12.2006087

KEYWORDS: Solar cells, Satellites, Space operations, Gallium arsenide, Photovoltaics, Solar concentrators, Silicon, Particles, Data modeling, Analytical research

Read Abstract +

Proceedings Article | 25 March 2013 Paper

Drift-diffusion modeling of InP-based triple junction solar cells

M. Lumb, M. González, C. Bailey, I. Vurgaftman, J. Meyer, J. Abell, M. Yakes, R. Hoheisel, J. Tischler, P. Stavrinou, M. Fuhrer, N. Ekins-Daukes, R. Walters

Proceedings Volume 8620, 86201G (2013) https://doi.org/10.1117/12.2005332

KEYWORDS: Solar cells, Sun, Coastal modeling, Analytical research, External quantum efficiency, Doping, Resistance, Germanium, Semiconducting wafers, Absorption

Read Abstract +

Proceedings Article | 15 October 2012 Paper

Quantum wells and superlattices for III-V photovoltaics and photodetectors

Matthew Lumb, Igor Vurgaftman, Chaffra Affouda, Jerry Meyer, Edward Aifer, Robert Walters

Proceedings Volume 8471, 84710A (2012) https://doi.org/10.1117/12.964654

KEYWORDS: Quantum wells, Superlattices, Solar cells, Stereolithography, Photodetectors, Electrons, Quantum efficiency, Photovoltaics, External quantum efficiency, Long wavelength infrared

Read Abstract +

Proceedings Article | 21 February 2012 Paper

Analysis of radiation hardness and subcell I-V characteristics of GaInP/GaAs/Ge solar cells using electroluminescence measurements

R. Hoheisel, S. Messenger, D. Scheiman, P. Jenkins, R. Walters

Proceedings Volume 8256, 82561X (2012) https://doi.org/10.1117/12.910031

KEYWORDS: Electroluminescence, Solar cells, Germanium, External quantum efficiency, Indium gallium phosphide, Gallium arsenide, Solar radiation, Particles, Solar energy, Analytical research

Read Abstract +

Proceedings Article | 21 February 2012 Paper

Simulation of novel InAlAsSb solar cells

Matthew Lumb, Maria Gonzalez, Igor Vurgaftman, Jerry Meyer, Joshua Abell, Michael Yakes, Raymond Hoheisel, Joseph Tischler, Phillip Jenkins, Paul Stavrinou, Markus Fuhrer, Ned Ekins-Daukes, Robert Walters

Proceedings Volume 8256, 82560S (2012) https://doi.org/10.1117/12.909324

KEYWORDS: Solar cells, Dielectrics, Solar energy, Binary data, Data modeling, Energy efficiency, Performance modeling, Refractive index, Gallium antimonide, External quantum efficiency

Read Abstract +

Proceedings Article | 21 February 2011 Paper

Modeling and analysis of multijunction solar cells

María González, Ngai Chan, Nicholas Ekins-Daukes, Jessica G. Adams, Paul Stavrinou, Igor Vurgaftman, Jerry Meyer, Joshua Abell, Robert Walters, Cory Cress, Phillip Jenkins

Proceedings Volume 7933, 79330R (2011) https://doi.org/10.1117/12.875757

KEYWORDS: Solar cells, Gallium arsenide, Multijunction solar cells, Solar energy, Indium gallium phosphide, Energy efficiency, Quantum wells, Coastal modeling, Performance modeling, Sun

Read Abstract +

Proceedings Article | 21 February 2011 Paper

Modeling of radiation induced defects in space solar cells

Robert Walters, Scott Messenger, Jeffrey Warner, Cory Cress, Maria Gonzalez, Serguei Maximenko

Proceedings Volume 7933, 79330P (2011) https://doi.org/10.1117/12.873902

KEYWORDS: Solar cells, Diffusion, Quantum efficiency, Silicon, Particles, Solar radiation, Solar energy, Gallium arsenide, Photovoltaics, Data modeling

Read Abstract +

SPIE Journal Paper | 1 March 2006

Photovoltaically powered modulating retroreflectors

Robert Walters, James Murphy, William Rabinovich, G. Charmaine Gilbreath, David Wilt, Mark Smith, Michael Krasowski, Phillip Jenkins, D. Scheiman, Jeffrey Warner, Scott Messenger, Justin Lorentzen, Geoffrey Summers

OE, Vol. 45, Issue 03, 034003, (March 2006) https://doi.org/10.1117/12.10.1117/1.2182127

KEYWORDS: Photovoltaics, Modulation, Retroreflectors, Sensors, Solar cells, Absorption, Photography, Binary data, Optical engineering, Telecommunications

Read Abstract +

Proceedings Article | 3 November 2004 Paper

Measurement and characterization of triple junction solar cells using a close matched multizone solar simulator

Jeffrey Warner, Robert Walters, Scott Messenger, Justin Lorentzen, Geoffrey Summers, Hector Cotal, Nassar Karam

Proceedings Volume 5520, (2004) https://doi.org/10.1117/12.559734

KEYWORDS: Calibration, Solar cells, Gallium arsenide, Quantum efficiency, Lamps, Indium gallium phosphide, Photovoltaics, Germanium, Optical filters, Light sources

Read Abstract +

Proceedings Article | 20 October 2004 Paper

Photovoltaically powered modulating retroreflectors

Robert Walters, James Murphy, William Rabinovich, G. Charmaine Gilbreath, David Wilt, Mark Smith, Michael Krasowski, Philip Jenkins, D. Scheiman, Jeffrey Warner, Scott Messenger, Justin Lorentzen, Geoffrey Summers

Proceedings Volume 5550, (2004) https://doi.org/10.1117/12.557299

KEYWORDS: Photovoltaics, Modulation, Solar cells, Sensors, Retroreflectors, Absorption, Binary data, Photography, Telecommunications, Indium gallium arsenide

Read Abstract +