Harold Paul Hjalmarson

Dr. Harold Paul Hjalmarson

orcid

Research Focus & Metrics

Academic Career Length

33Years (1994-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 January 2025 in Applied Sciences
Verified
Journal Article
Open access
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VMVincent E Meyers
Vincent E Meyers
LVLars Voss
Lars Voss
JFJack Flicker
Jack Flicker
LRLuciano Garcia Rodriguez
Luciano Garcia Rodriguez
HHHarold Paul Hjalmarson
Harold Paul Hjalmarson
RKRobert Kaplar
Robert Kaplar
Photoconductive semiconductor switching (PCSS) devices have unique characteristics to address the growing need for electrically isolated, optically gated, picosecond-scale jitter devices capable of operating at high voltage, current, and frequency. The state of the art in material selection, doping, triggering, and system integration in PCSSs is presented. The material properties and doping considerations of GaN, GaAs, SiC, diamond, and β-Ga2O3 in the fabrication of PCSS devices are discussed. A review of the current understanding of the physics of the high-gain mode known as lock-on is presented.

15 June 1996 in Physical Review B
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Journal Article
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JNJ. S. Nelson
J. S. Nelson
EJE. D. Jones
E. D. Jones
SMS. M. Myers
S. M. Myers
DFD. M. Follstaedt
D. M. Follstaedt
HHHarold Paul Hjalmarson
Harold Paul Hjalmarson
KCK. W. Carey
K. W. Carey
A number of complementary experimental characterization tools and theoretical band structure methods were used to determine unambiguously the band-edge luminescence as a function of Al concentration, and to place an upper limit on the short-wavelength emission of InAlGaP alloys lattice matched to GaAs. In particular, the direct-to-indirect band-gap crossing has been determined by analyzing a series of metalorganic vapor-phase-epitaxy-grown In0.49(Aly Ga1−y )0.51P alloys lattice matched to GaAs with double-crystal x-ray analysis, Rutherford backscattering spectroscopy, pressure- and temperature-dependent photoluminescence, and transmission electron microscopy. The experimental measurements are compared to first-principles plane-wave pseudopotential band structure calculations for the ternary end points, InGaP and InAlP. The maximum room temperature direct band gap is found to be 2.24 eV, corresponding to an Al composition of y=0.52±0.02, in good agreement with the theoretical prediction of 0.58±0.05. © 1996 The American Physical Society.

1 July 1994 in IEEE Transactions on Electron Devices
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Journal Article
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JZJ.C. Zolper
J.C. Zolper
ABA.G. Baca
A.G. Baca
RSR.J. Shul
R.J. Shul
AHA.J. Howard
A.J. Howard
DRD.J. Rieger
D.J. Rieger
VHV.M. Hietala
V.M. Hietala

24 May 2023
Verified
Book Chapter
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JFJack Flicker
Jack Flicker
LRLuciano Garcia Rodriguez
Luciano Garcia Rodriguez
JMJacob Mueller
Jacob Mueller
LGLee Gill
Lee Gill
JNJason C. Neely
Jason C. Neely
RKRobert Kaplar
Robert Kaplar

1 July 2025
Verified
Report
Closed access
A(Albuquerque Sandia National Laboratories (Snl-Nm)
Albuquerque Sandia National Laboratories (Snl-Nm)
KSKeshab Sapkota
Keshab Sapkota
U(Usdoe National Nuclear Security Administration (Nnsa)
Usdoe National Nuclear Security Administration (Nnsa)
GWGeorge Wang
George Wang
GVGyorgy Vizkelethy
Gyorgy Vizkelethy
HHHarold Paul Hjalmarson
Harold Paul Hjalmarson

1 February 2022
Verified
Conference Paper
Open access
PDF file
PAP. Apsangi
P. Apsangi
SRS. Roark
S. Roark
APA. Privat
A. Privat
HHHarold Paul Hjalmarson
Harold Paul Hjalmarson
HBH. J. Barnaby
H. J. Barnaby
Keith E. HolbertKeith E. Holbert
Keith E. Holbert
Radiation-induced interface trap buildup is a strong function of hydrogen content in the semiconductor materials, which is quantitatively mapped to percent of hydrogen in the semiconductor packaging using a combination of experimental and simulation-base approaches.