Coulomb crystals of charged liquid droplets have been created in a Paul trap at atmospheric pressure. The technique improves upon similar experiments with solid dust particles by having a controlled and reproducible charge-to-mass ratio. The charge-to-mass ratio of the droplets, the spatial configurations of small crystals, and the frequency of the center-of-mass mode of oscillation have been determined.
REFERENCES
1.
R. F.
Wuerker
, H.
Shelton
, and R. V.
Langmuir
, “Electrodynamic Containment of Charged Particles
,” J. Appl. Phys.
30
, 342
–349
(1959
).2.
See, for example,
D. A.
Church
, “Collision measurements and excited-level lifetime measurements on ions stored in Paul, Penning and Kingdon traps
,” Phys. Rep.
228
, 253
–358
(1993
).3.
T. G.
Owe Berg
and T. A.
Gaukler
, “Apparatus for the study of charged particles and droplets
,” Am. J. Phys.
37
, 1013
–1018
(1969
).4.
H.
Winter
and H. W.
Ortjohann
, “Simple demonstration of storing macroscopic particles in a Paul trap
,” Am. J. Phys.
59
, 807
–813
(1991
).5.
J. J.
Bollinger
, D. J.
Wineland
, and D. H. E.
Dubin
, “Non-neutral ion plasmas and crystals, laser cooling, and atomic clocks
,” Phys. Plasmas
1
, 1403
–1414
(1994
).6.
A.
Rahman
and J. P.
Schiffer
, “Structure of a one-component plasma in an external field: A molecular-dynamics study for particle arrangement in a heavy ion storage ring
,” Phys. Rev. Lett.
57
, 1133
–1136
(1986
).7.
G. S.
Stringfellow
, H. E.
DeWitt
, and W. L.
Slattery
, “Equation of state of the one-component plasma derived from precision Monte Carlo calculations
,” Phys. Rev. A
41
, 1105
–1111
(1990
).8.
D. H. E.
Dubin
, “Correlation energies of simple bounded Coulomb lattices
,” Phys. Rev. A
40
, 1140
–1143
(1989
).9.
R.
Rafac
, J. P.
Schiffer
, J. S.
Hangst
, D. H. E.
Dubin
, and D. J.
Wales
, “Stable configurations of confined cold ionic systems
,” Proc. Natl. Acad. Sci. USA
88
, 483
–486
(1991
).10.
R. W.
Hasse
and V. V.
Avilov
, “Structure and Madelung energy of spherical Coulomb crystals
,” Phys. Rev. A
44
, 4506
–4515
(1991
).11.
12.
S.
Arnold
and L. M.
Folan
, “Fluorescence spectrometer for a single electrodynamically levitated microparticle
,” Rev. Sci. Instrum.
57
, 2250
–2253
(1986
).13.
J.
Hoffnagle
and R. G.
Brewer
, “Frequency-locked motion of two particles in a Paul Trap
,” Phys. Rev. Lett.
71
, 1828
–1831
(1993
).14.
D. J.
Wineland
, J. C.
Bergquist
, Wayne M.
Itano
, J. J.
Bollinger
, and C. H.
Manney
, “Atomic-Ion Coulomb Clusters in an Ion Trap
,” Phys. Rev. Lett.
59
, 2935
–2938
(1987
).15.
R.
Blümel
, C.
Kappler
, W.
Quint
, and H.
Walther
, “Chaos and order of laser-cooled ions in a Paul trap
,” Phys. Rev. A
40
, 808
–823
(1989
).16.
J. J.
Bollinger
, D. J.
Heinzen
, F. L.
Moore
, Wayne M.
Itano
, D. J.
Wineland
, and D. H. E.
Dubin
, “Electrostatic modes of ion-trap plasmas
,” Phys. Rev. A
48
, 525
–545
(1993
).17.
S. L.
Gilbert
, J. J.
Bollinger
, and D. J.
Wineland
, “Shell-Structure Phase of Magnetically Confined Strongly Coupled Plasmas
,” Phys. Rev. Lett.
60
, 2022
–2025
(1988
).18.
J. N.
Tan
, J. J.
Bollinger
, B.
Jelenkovic
, and D. J.
Wineland
, “Long-range order in laser-cooled, atomic-ion Wigner crystals observed by Bragg scattering
,” Phys. Rev. Lett.
75
, 4198
–4201
(1995
).19.
G. S.
Selwyn
, J.
Singh
, and R. S.
Bennett
, “In situ laser diagnostic studies of plasma-generated particulate contamination
,” J. Vac. Sci. Technol. A
7
, 2758
–2765
(1989
).20.
R. T.
Farouki
and S.
Hamaguchi
, “Phase transitions of dense systems of charged ‘dust’ grains in plasmas
,” Appl. Phys. Lett.
61
, 2973
–2975
(1992
), and references therein.21.
H.
Thomas
, G. E.
Morfill
, V.
Demmel
, J.
Goree
, B.
Feuerbacher
, and D.
Möhlmann
, “Plasma crystal: Coulomb crystallization in a dusty plasma
,” Phys. Rev. Lett.
73
, 652
–655
(1994
).22.
A.
Melzer
, T.
Trottenberg
, and A.
Piel
, “Experimental determination of the charge on dust particles forming Coulomb lattices
,” Phys. Lett. A
191
, 301
–308
(1994
).23.
J. H.
Chu
and L.
I
, “Direct observation of Coulomb crystals in strongly coupled rf dusty plasmas
,” Phys. Rev. Lett.
72
, 4009
–4012
(1994
).24.
A.
Melzer
, A.
Homann
, and A.
Piel
, “Experimental investigations of the melting transition of the plasma crystal
,” Phys. Rev. E
53
, 2757
–2765
(1996
).25.
H. M.
Thomas
and G. E.
Morfill
, “Melting Dynamics of a Plasma Crystal
,” Nature (London)
379
, 806
–809
(1996
).26.
A.
Barkan
, R. L.
Merlino
, and N.
D’Angelo
, “Laboratory observations of the dust-acoustic wave mode
,” Phys. Plasmas
2
, 3563
–3565
(1995
).27.
J. B.
Pieper
and J.
Goree
, “Dispersion of plasma dust acoustic waves in the strong coupling regime
,” Phys. Rev. Lett.
77
, 3137
–3140
(1996
).28.
C.-H.
Chiang
and L.
I
, “Cooperative particle motions and dynamical behaviors of free dislocations in strongly coupled quasi-2D dusty plasmas
,” Phys. Rev. Lett.
77
, 647
–650
(1996
).29.
V. E.
Fortov
, A. P.
Nefedov
, O. F.
Petrov
, A. A.
Samarian
, and A. V.
Chernyschev
, “Particle ordered structures in a strongly coupled classical thermal plasma
,” Phys. Lett. A
219
, 89
–94
(1996
).30.
H. G.
Dehmelt
, “Radiofrequency spectroscopy of stored ions. I. Storage
,” Adv. At. Mol. Phys.
3
, 53
–72
(1967
).31.
D. J.
Wineland
, W. M.
Itano
, and R. S.
Van Dyck
, Jr., “High resolution spectroscopy of stored ions
,” Adv. At. Mol. Phys.
19
, 135
–186
(1983
).32.
I.
Siemers
, R.
Blatt
, Th.
Sauter
, and W.
Neuhauser
, “Dynamics of ion clouds in Paul traps
,” Phys. Rev. A
38
, 5121
–5128
(1988
).33.
H.
Walther
, “Phase transitions of stored laser-cooled ions
.” Adv. At., Mol., Opt. Phys.
31
, 137
–182
(1993
).34.
G. Schmidt, Physics of High Temperature Plasmas (Academic, New York, 1979), p. 47.
35.
Errors arising from using simple electrodes are discussed in
E. C.
Beaty
, J. Appl. Phys.
61
, 2118
–2122
(1987
).36.
J.
Zeleny
, “Instability of Electrified Liquid Surfaces
,” Phys. Rev.
10
, 1
–6
(1917
).37.
R. G.
Sweet
, “High frequency recording with electrostatically deflected ink jets
,” Rev. Sci. Instrum.
36
, 131
–136
(1965
).38.
J. M.
Schneider
, N. R.
Lindblad
, C. D.
Hendricks
, Jr., and J. M.
Crowley
, “Stability of an electrified liquid jet
,” J. Appl. Phys.
38
, 2599
–2605
(1967
).39.
M.
Mutoh
, S.
Kaieda
, and K.
Kamimura
, “Convergence and disintegration of liquid jets induced by an electrostatic field
,” J. Appl. Phys.
50
, 3174
–3179
(1979
).40.
R. J.
Pfeifer
and C. D.
Hendricks
, “Charge-to-mass relationships for electrohydrodynamically sprayed liquid droplets
,” Phys. Fluids
10
, 2149
–2154
(1967
).41.
A. R.
Jones
and K. C.
Thong
, “The production of charged monodisperse fuel droplets by electrical dispersion
,” J. Phys. D
4
, 1159
–1166
(1971
).42.
M.
Cloupeau
and B.
Prunet-Foch
, “Electrostatic spraying of liquids in the cone-jet mode
,” J. Electrost.
22
, 135
–139
(1989
).43.
K.
Tang
and A.
Gomez
, “On the structure of an electrostatic spray of monodisperse droplets
,” Phys. Fluids
6
, 2317
–2332
(1994
).44.
Lord
Rayleigh
, “On the equilibrium of liquid conducting masses charged with electricity
,” Philos. Mag.
14
, 184
–186
(1882
).45.
A.
Gomez
and K.
Tang
, “Charge and fission of droplets in electrostatic sprays
,” Phys. Fluids
6
, 404
–414
(1994
).46.
D. J.
Wineland
, W. M.
Itano
, J. C.
Bergquist
, and R. G.
Hulet
, “Laser-cooling limits and single-ion spectroscopy
,” Phys. Rev. A
36
, 2220
–2232
(1987
).47.
B.
Walch
, M.
Horányi
, and S.
Robertson
, “Measurement of the Charging of Individual Dust Grains in a Plasma
,” IEEE Trans. Plasma Sci.
22
, 97
–102
(1994
). The Faraday cup circuit is similar to that in Fig. 4 of this reference, however, the feedback resistance is reduced from 200 to 5 megohms to increase the frequency response.48.
J. D.
Prestage
, A.
Williams
, L.
Maleki
, M. J.
Djomehri
, and E.
Harabetian
, “Dynamics of charged particles in a Paul radio frequency quadrupole trap
,” Phys. Rev. Lett.
66
, 2964
–2967
(1991
).
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