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D. T. Young, J. E. Nordholt,
J. L. Burch,
D. J. McComas,
R. P. Bowman,
R. A. Abeyta,
J. Alexander,
J. Baldonado,
P. Barker,
R. K. Black, [......],
B. P. Henneke,
E. F. Horton,
D. J. Lawrence,
K. P. McCabe,
D. Reisenfeld,
R. P. Salazar,
M. Shappirio,
S. A. Storms,
C. Urdiales,
J. H. Waite
[show abstract]
[hide abstract]
ABSTRACT: The Plasma Experiment for Planetary Exploration (PEPE) flown on Deep Space 1 combines an ion mass spectrometer and an electron
spectrometer in a single, low-resource instrument. Among its novel features PEPE incorporates an electrostatically swept field-of-view
and a linear electric field time-of-flight mass spectrometer. A significant amount of effort went into developing six novel
technologies that helped reduce instrument mass to 5.5 kg and average power to 9.6 W. PEPE’s performance was demonstrated
successfully by extensive measurements made in the solar wind and during the DS1 encounter with Comet 19P/Borrelly in September
2001.
Space Science Reviews 04/2012; 129(4):327-357. · 3.61 Impact Factor
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K D McKeegan,
A P A Kallio,
V S Heber,
G Jarzebinski,
P H Mao,
C D Coath,
T Kunihiro,
R C Wiens, J E Nordholt,
R W Moses,
D B Reisenfeld,
A J G Jurewicz,
D S Burnett
[show abstract]
[hide abstract]
ABSTRACT: All planetary materials sampled thus far vary in their relative abundance of the major isotope of oxygen, (16)O, such that it has not been possible to define a primordial solar system composition. We measured the oxygen isotopic composition of solar wind captured and returned to Earth by NASA's Genesis mission. Our results demonstrate that the Sun is highly enriched in (16)O relative to the Earth, Moon, Mars, and bulk meteorites. Because the solar photosphere preserves the average isotopic composition of the solar system for elements heavier than lithium, we conclude that essentially all rocky materials in the inner solar system were enriched in (17)O and (18)O, relative to (16)O, by ~7%, probably via non-mass-dependent chemistry before accretion of the first planetesimals.
Science 06/2011; 332(6037):1528-32. · 31.20 Impact Factor
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T E Chapuran,
P Toliver,
N A Peters,
J Jackel,
M S Goodman,
R J Runser,
S R McNown,
N Dallmann,
R J Hughes,
K P McCabe, J E Nordholt,
C G Peterson,
K T Tyagi,
L Mercer,
H Dardy
[show abstract]
[hide abstract]
ABSTRACT: Modern optical networking techniques have the potential to greatly extend the applicability of quantum communications by moving beyond simple point-to-point optical links and by leveraging existing fibre infrastructures. We experimentally demonstrate many of the fundamental capabilities that are required. These include optical-layer multiplexing, switching and routing of quantum signals; quantum key distribution (QKD) in a dynamically reconfigured optical network; and coexistence of quantum signals with strong conventional telecom traffic on the same fibre. We successfully operate QKD at 1310 nm over a fibre shared with four optically amplified data channels near 1550 nm. We identify the dominant impairment as spontaneous anti-Stokes Raman scattering of the strong signals, quantify its impact, and measure and model its propagation through fibre. We describe a quantum networking architecture which can provide the flexibility and scalability likely to be critical for supporting widespread deployment of quantum applications.
New Journal of Physics 10/2009; 11(10):105001. · 4.18 Impact Factor
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N A Peters,
P Toliver,
T E Chapuran,
R J Runser,
S R McNown,
C G Peterson,
D Rosenberg,
N Dallmann,
R J Hughes,
K P McCabe, J E Nordholt,
K T Tyagi
[show abstract]
[hide abstract]
ABSTRACT: To move beyond dedicated links and networks, quantum communications signals must be integrated into networks carrying classical optical channels at power levels many orders of magnitude higher than the quantum signals themselves. We demonstrate the transmission of a 1550 nm quantum channel with up to two simultaneous 200 GHz spaced classical telecom channels, using reconfigurable optical add drop multiplexer (ROADM) technology for multiplexing and routing quantum and classical signals. The quantum channel is used to perform quantum key distribution (QKD) in the presence of noise generated as a by-product of the co-propagation of classical channels. We demonstrate that the dominant noise mechanism can arise from either four-wave mixing or spontaneous Raman scattering, depending on the optical path characteristics as well as the classical channel parameters. We quantify these impairments and discuss mitigation strategies.
New Journal of Physics 04/2009; 11(4):045012. · 4.18 Impact Factor
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D. Rosenberg,
C. G. Peterson,
J. W. Harrington,
P. R. Rice,
N. Dallmann,
K. T. Tyagi,
K. P. McCabe,
S. Nam,
B. Baek,
R. H. Hadfield,
R. J. Hughes, J. E. Nordholt
[show abstract]
[hide abstract]
ABSTRACT: Quantum key distribution (QKD) has the potential for widespread real-world applications. To date no secure long-distance experiment has demonstrated the truly practical operation needed to move QKD from the laboratory to the real world due largely to limitations in synchronization and poor detector performance. Here we report results obtained using a fully automated, robust QKD system based on the Bennett Brassard 1984 protocol (BB84) with low-noise superconducting nanowire single-photon detectors (SNSPDs) and decoy levels. Secret key is produced with unconditional security over a record 144.3 km of optical fibre, an increase of more than a factor of five compared to the previous record for unconditionally secure key generation in a practical QKD system. Comment: 9 pages
06/2008;
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[show abstract]
[hide abstract]
ABSTRACT: We have implemented decoy state quantum key distribution over a recordsetting 107 km of dark optical fiber in a switched interferometer phase-encoding system utilizing ultra-low-noise, high-efficiency transition-edge sensors.
Quantum Electronics and Laser Science Conference, 2007. QELS '07; 06/2007
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[show abstract]
[hide abstract]
ABSTRACT: Use of low-noise detectors can both increase the secret bit rate of long-distance quantum key distribution (QKD) and dramatically extend the length of a fibre optic link over which secure keys can be distributed. Previous work has demonstrated the use of ultra-low-noise transition-edge sensors (TESs) in a QKD system with transmission over 50 km. In this study, we demonstrate the potential of the TESs by successfully generating an error-corrected, privacy-amplified key over 148.7 km of dark optical fibre at a mean photon number μ = 0.1, or 184.6 km of dark optical fibre at a mean photon number of 0.5. We have also exchanged secret keys over 67.5 km that is secure against powerful photon-number-splitting (PNS) attacks.
New Journal of Physics 09/2006; 8(9):193. · 4.18 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Use of low-noise detectors can both increase the secret bit rate of long-distance quantum key distribution (QKD) and dramatically extend the length of a fibre optic link over which secure key can be distributed. Previous work has demonstrated use of ultra-low-noise transition-edge sensors (TESs) in a QKD system with transmission over 50 km. In this work, we demonstrate the potential of the TESs by successfully generating error-corrected, privacy-amplified key over 148.7 km of dark optical fibre at a mean photon number mu = 0.1, or 184.6 km of dark optical fibre at a mean photon number of 0.5. We have also exchanged secret key over 67.5 km that is secure against powerful photon-number-splitting attacks. Comment: 7 pages, 4 figures
07/2006;
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N.I. Nweke,
R.J. Runser,
S.R. McNown,
J.B. Khurgin,
T.E. Chapuran,
P. Toliver,
M.S. Goodman,
J. Jackel,
R.J. Hughes,
C.G. Peterson, J.E. Nordholt
[show abstract]
[hide abstract]
ABSTRACT: An EDFA bypass and filtering architecture is demonstrated , allowing a 1310 nm QKD channel to be transmitted over the same fiber as four 1.5 mum WDM channels which are amplified in mid-span.
Lasers and Electro-Optics, 2006 and 2006 Quantum Electronics and Laser Science Conference. CLEO/QELS 2006. Conference on; 06/2006
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N. I. Nweke,
P. Toliver,
R. J. Runser,
S. R. McNown,
J. B. Khurgin,
T. E. Chapuran,
M. S. Goodman,
R. J. Hughes,
C. G. Peterson,
K. McCabe, J. E. Nordholt,
K. Tyagi,
P. Hiskett,
N. Dallmann
[show abstract]
[hide abstract]
ABSTRACT: Quantum key distribution (QKD) is a new technique for secure key distribution based on the laws of physics rather than mathematical or algorithmic computational complexity used by current systems. Understanding the compatibility of QKD at 1310 nm with the existing commercial optical networks bearing classical wavelength-division-multiplexed (WDM) channels at 1550 nm is important to advance the deployment of QKD systems in such networks. The minimum wavelength separation for multiplexing QKD and WDM channels on a shared fiber is experimentally determined for impairment-free QKD+WDM transmission.
Applied Physics Letters 10/2005; 87(17):174103-174103-3. · 3.84 Impact Factor
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T. E. Chapuran,
P. Toliver,
R. J. Runser,
S. R. McNown,
M. S. Goodman,
N. Nweke,
J. Jackel,
R. J. Hughes,
C. G. Peterson,
K. McCabe, J. E. Nordholt,
K. Tyagi,
P. Hiskett,
N. Dallmann,
L. Mercer,
H. Dardy
[show abstract]
[hide abstract]
ABSTRACT: Quantum key distribution (QKD) is an emerging technology for secure distribution of keys between users linked by free-space or fiber optic transmission facilities. QKD has usually been designed for and operated over dedicated point-to-point links. However, the commercial world has been developing increasingly sophisticated fiber networks, with basic networking functions such as routing and multiplexing performed in the optical domain. One of the most important practical questions for the future of QKD is to what extent it can benefit from these trends, either to expand the capabilities of dedicated quantum networks, or to avoid the need for dedicated networks by combining quantum and conventional optical signals onto a single infrastructure.
In this paper, we report on systematic investigations of these issues using a 1310-nm weak-coherent, phase-encoded B92 prototype QKD system developed by Los Alamos that includes the implementation of error correction, privacy amplification, and authentication. We have demonstrated reconfigurability of QKD networks via optical switching and successful QKD operation in the presence of amplified DWDM signals over 10 km of fiber. We have identified anti-Stokes Raman scattering of the DWDM signals in the fiber as a dominant transmission impairment for QKD, and developed filtering architectures to extend transmission distances to at least 25 km. We have also measured noise backgrounds and polarization variations in network fibers to understand applicability to real-world networks. We will discuss the implications of our results for the choice of QKD wavelengths, wavelength-spacing between QKD and conventional channels, and QKD network architectures.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
05/2005;
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P. Toliver,
R.J. Runser,
T.E. Chapuran,
S. McNown,
M.S. Goodman,
J. Jackel,
R.J. Hughes,
C.G. Peterson,
K. McCabe, J.E. Nordholt,
K. Tyagi,
P. Hiskett,
N. Dallman
[show abstract]
[hide abstract]
ABSTRACT: This study presents an experimental demonstration of 1310 nm QKD multiplexing and transmission with amplified DWDM signals over a shared 10 km fiber span. This work identifies anti-Stokes Raman scattering generated during fiber propagation as the primary contributor of crosstalk noise at the QKD receiver. New results are presented on the characterization of spontaneous anti-Stokes Raman noise (SASRN), generated within the fiber by the high-power DWDM signals, and implications for QKD+DWDM networking architectures are also discussed.
Lasers and Electro-Optics Society, 2004. LEOS 2004. The 17th Annual Meeting of the IEEE; 12/2004
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R.J. Runse,
P. Toliver,
S. McNown,
T.E. Chapuran,
M.S. Goodman,
J. Jackel,
R.J. Hughes, J.E. Nordholt,
C.G. Peterson,
K. Tyagi,
P. Hiskett,
K. McCabe
Optical Fiber Measurements, 2004. Technical Digest: Symposium on; 02/2004
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D T Young,
F J Crary, J E Nordholt,
F Bagenal,
D Boice,
J L Burch,
A Eviatar,
R Goldstein,
J J Hanley,
D J Lawrence,
D J Mccomas,
R Meier,
D Reisenfeld,
K Sauer,
R C Wiens
[show abstract]
[hide abstract]
ABSTRACT: The Plasma Experiment for Planetary Exploration (PEPE) made detailed observations of the plasma environment of Comet 19P/Borrelly during the Deep Space 1 (DS1) flyby on September 22, 2001. Several distinct regions and boundaries have been identified on both inbound and outbound trajectories, including an upstream region of decelerated solar wind plasma and cometary ion pickup, the cometary bow shock, a sheath of heated and mixed solar wind and cometary ions, and a collisional inner coma dominated by cometary ions. All of these features were significantly offset to the north of the nucleus–Sun line, suggesting that the coma itself produces this offset, possibly because of well-collimated large dayside jets directed 8 • –10 • northward from the nucleus as observed by the DS1 MICAS camera. The maximum observed ion density was 1640 ion/cm 3 at a distance of 2650 km from the nucleus while the flow speed dropped from 360 km/s in the solar wind to 8 km/s at closest approach. Preliminary analysis of PEPE mass spectra suggest that the ratio of CO + /H 2 O + is lower than that observed with Giotto at 1P/Halley.
Icarus 01/2004; 167:80-88. · 3.38 Impact Factor
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P. Toliver,
R.J. Runser,
T.E. Chapuran,
J.L. Jackel,
T.C. Banwell,
M.S. Goodman,
R.J. Hughes,
C.G. Peterson,
D. Derkacs, J.E. Nordholt,
L. Mercer,
S. McNown,
A. Goldman,
J. Blake
[show abstract]
[hide abstract]
ABSTRACT: Quantum key distribution (QKD) enables unconditional physical layer security for the distribution of cryptographic key material. However, most experimental demonstrations have relied on simple point-to-point optical links. In this paper we investigate the compatibility of QKD with reconfigurable optical networks. By performing the first tests of QKD transmission through optical switches, we study if there are impairment mechanisms other than switch insertion loss that impact the sifted and error corrected secret bit yield. Three types of transparent optical switch elements are investigated including lithium niobate (LiNbO/sub 3/), microelectromechanical systems (MEMS), and optomechanical. We show that QKD can be extended beyond point-to-point links to switched multinode architectures including protected ring networks to enhance quantum channel availability.
IEEE Photonics Technology Letters 12/2003; · 2.19 Impact Factor
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M.S. Goodman,
P. Toliver,
R.J. Runser,
T.E. Chapuran,
J. Jackel,
R.J. Hughes,
C.G. Peterson,
K. McCabe, J.E. Nordholt,
K. Tyagi,
P. Hiskett,
S. McNown,
N. Nweke,
J.T. Blake,
L. Mercer,
H. Dardy
[show abstract]
[hide abstract]
ABSTRACT: In this paper, we demonstrate for the first time, the coexistence architectures which enable quantum cryptographic systems to use the emerging optical network infrastructure. A vision of a future network that combines classical optical communications with ultra-low power quantum signals over a shared, reconfigurable fiber infrastructure is illustrated. We have used a fiber quantum key distribution (QKD) system to experimentally measure the effective QKD throughput for various types of optical switch elements, including opto-mechanical, lithium niobate, and 2D MEMS. We have investigated QKD coexistence with a commercial EDFA-amplified DWDM system using the experimental setup. These results are an important first step for scaling QKD beyond dedicated point-to-point fiber links and provide a context for understanding the applicability of QKD to the broader optical networking environment.
Lasers and Electro-Optics Society, 2003. LEOS 2003. The 16th Annual Meeting of the IEEE; 11/2003
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[show abstract]
[hide abstract]
ABSTRACT: Cometary compositions are of great interest because they hold important
clues to the formation of the outer solar system, and to the sources of
volatiles in the solar system, including the terrestrial planets. In
order to understand the primordial compositions of cometary nuclei, it
is important to also understand their evolution, as many of the comets
most accessible to spacecraft are highly evolved. It is also important
to understand the ion and neutral chemistry that occurs in the coma
surrounding the nucleus if the coma ion composition is to be used to
determine the original composition of the nucleus. Deep Space One
(DS1) was only the second spacecraft, after Giotto, to use an ion
mass-resolving instrument to explore cometary coma compositions in-situ,
which it did during the flyby of Comet Borrelly on September 22, 2001.
Borrelly is significantly more evolved than Halley. In addition, the
encounter occurred at a significantly greater distance from the sun
(1.36 AU vs 0.9 AU for Giotto at Halley). The Plasma Experiment for
Planetary Exploration (PEPE) on board DS1 was capable of resolving
electron and ion energy, angle of incidence, and ion mass composition.
The PEPE ion data from the seven minutes surrounding closest approach
(2171 km) have been extensively analyzed. The instrument response was
modeled using SIMION and TRIM codes for all of the major species through
20 AMU plus CO (at its operating voltage PEPE was very insensitive to
heavier molecules). Chi-squared minimization analysis is being carried
out to determine the best fit and the uncertainties. Preliminary
results for the predominant heavy ions are OH+ at (72 +/-
9)% of the total water-group ion density, H2O+ at
(25 +/- 7)%, CH3+ at (5 +/- 3)%, and O+
at (4 +/- 5)%. Uncertainties are quoted at the 90% confidence level.
Comparison with reported Halley compositions from Giotto shows that
Borrelly clearly has a lower H3O+ abundance (<
9%), consistent with a more evolved comet. The presence of relatively
high amounts of CH3+, proposed in the context of
Halley to be produced by protonation of CH2+, is
somewhat surprising in this context. Because the
H3O+/H2O+ ratio is an
indicator of the degree of protonation in the coma, a low
H3O+/H2O+ ratio would
predict a low CH3+/CH2+
ratio as well. However, this is not the case at Borrelly. The
CH3+/H3O+ ratio will need
further study in future comet models and observations.
AGU Fall Meeting Abstracts. 11/2002; -1:0381.
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[show abstract]
[hide abstract]
ABSTRACT: Summary form only given. The Los Alamos free-space quantum key distribution (QKD) system operates at a 1-MHz clock rate. On each clock cycle a ∼1-ns "bright timing pulse" is emitted from an array of ∼1550-nm lasers at the transmitter ("Alice"). After a ∼100 ns delay one of four temperature-controlled "data" diode lasers emits a ∼1-ns, 772-nm optical pulse that is attenuated to the single-photon level. We present results from operations over multi-kilometer atmospheric ranges. The spectral, spatial and temporal filtering allow practical secret bit rates even in full daylight. We also present a study of a satellite-to-ground QKD system, and an analysis of the expected secret bit rate.
Quantum Electronics and Laser Science Conference, 2002. QELS '02. Technical Digest. Summaries of Papers Presented at the; 02/2002
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[show abstract]
[hide abstract]
ABSTRACT: An experimental free-space quantum key distribution (QKD) system has been tested over an outdoor optical path of ~ 1 km under
nighttime conditions at Los Alamos National Laboratory. This system employs the Bennett 92 protocol; here we give a brief
overview of this protocol, and describe our experimental implementation of it. An analysis of the system efficiency is presented,
as well as a description of our error detection protocol, which employs a two-dimensional parity check scheme. Finally, the
susceptibility of this system to eavesdropping by various techniques is determined. Possible applications include the rekeying
of satellites in low earth orbit.
12/2001: pages 367-374;
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D. T. Young,
F. J. Crary, J. E. Nordholt,
J. J. Hanley,
J. L. Burch,
D. J. McComas,
R. Goldstein,
D. Boice,
R. C. Wiens,
D. R. Lawrence,
A. Eviatar,
K. Sauer,
R. Meier
[show abstract]
[hide abstract]
ABSTRACT: On September 22, 2001, the Deep Space 1 spacecraft flew through the coma
of Comet 19P/Borrelly, coming within 2154 km of the central nucleus at a
relative velocity of 16.6 km/s. We report here on initial analysis of
solar wind and cometary pickup ions measured by the Plasma Experiment
for Planetary Exploration (PEPE) onboard DS1. PEPE is a novel
energy-angle-mass/charge spectrometer that simultaneously measures ions
and electrons over the energy range few eV to 32 keV/q and the M/q range
1 to 100 amu/e. Ion and electron data indicate a very strong interaction
between the solar wind and cometary pickup ions leading to slowing of
the solar wind from 320 km/s prior to the encounter to 10 km/s. A
significant finding is that the ion flow field is not symmetric with
respect to the nucleus-sun line, but rather is displaced a few thousand
kilometers northward of it. It is possible that the strong jets observed
in the DS1 images of the nucleus are related to the observed ion flow
asymmetry.
10/2001; 33:1087.
