Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Microwave-cavity modes directly observed in a Penning trap

Robert S. Van Dyck, Fred L. Moore, Dean L. Farnham, Paul B. Schwinberg, HANS G. DEHMELT

Published Oct 1, 1987• 13 citations
Publisher

Abstract

The microwave-cavity mode pattern has been directly observed in an old-style compensated Penning trap by a simple bolometric technique which monitors changes in the temperature of the axial center-of-mass motion for a cloud of electrons. The method allows one to easily determine the position of individual modes to a precision better than 0.01%. Presently, over 60 modes have been observed for fields between 17 and 60 kG and an upper limit estimate of 2300 has been made for the cavity Q.

DOI
10.1103/physreva.36.3455

Related papers

Single-Particle Self-Excited Oscillator

Brian D’Urso, Ramon van Handel, Brian Odom +2 more

Electronic feedback is used to self-excite the axial oscillation of a single electron in a Penning trap. Large, stable, easily detected oscillations arise even in an anharmonic potential. Amplitudes are controlled by adjusting the feedback gain, and frequencies can be made nearly independent of amplitude fluctuations. Quantum jump spectroscopy of a perpendicular cyclotron motion reveals the absolute temperature and amplitude of the self-excited oscillation. The possibility to quickly measure parts per billion frequency shifts could open the way to improved measurements of e(-), e(+), p, and (-)p magnetic moments.

Physical Review Letters•Mar 23, 2005•34 citations

Cooling and self-excitation of a one-electron oscillator

Brian D’Urso

With a superposition of static electric and magnetic fields, a Penning trap can confine a single electron indefinitely. A weak coupling of the electron to its environment makes the system ideal for precision measurements but renders detection of the electron’s motion difficult. In order to measure fundamental properties of an electron, we employ a Penning trap cooled by a dilution refrigerator. This experimental setup requires extremely low-noise and low-power cryogenic amplifiers for detection of the electron’s axial motion. We design and demonstrate new amplifiers, resulting in a significant decrease of the axial temperature and in an improved signal to noise ratio. We use feedback to cool the axial motion and to self-excite the axial motion for continuous monitoring of the axial frequency. These techniques for cooling and measuring the axial frequency may contribute to an improved measurement of the electron g factor, a more stringent CPT test in leptons, and a more precise measurement of the proton-electron mass ratio.

•Jan 1, 2003•11 citations

Observation of intense nonclassical field of Mandel Q as low as -0.6 in the cavity QED microlaser

송영훈

•Jan 1, 2019•0 citations

Microwave Squeezing Beyond 3 dB

Marric Stephens

Researchers suppress measurement fluctuations of microwaves in a cavity to below that of vacuum.

Physics•May 20, 2021•0 citations

Dynamics of an unbalanced two-ion crystal in a Penning trap for application in optical mass spectrometry

M. J. Gutiérrez, J. Berrocal, Francisco Domínguez +4 more

In this paper, the dynamics of an unbalanced two-ion crystal comprising the ``target'' and the ``sensor'' ions confined in a Penning trap along the magnetic-field axis has been studied. First, the low amplitude regime is addressed. In this regime, the overall potential including the Coulomb repulsion between the ions can be considered harmonic and the axial, magnetron, and reduced-cyclotron modes split up into the so-called stretch and common modes, that are generalizations of the well-known ``breathing'' and ``center-of-mass'' motions of a balanced crystal made of two ions. By using optical detection to measure the frequencies of the modes of the crystal, and of the sensor ion on its own, in the quantum regime of motion, it will be possible to determine the target ion's free-cyclotron frequency. The nonharmonicity of the Coulomb interaction is also discussed since this causes large systematic effects, which are minimized due to the high sensitivity of the optical detection method when the crystal is cooled to the ground state of motion in the Penning trap.

arXiv:1907.08045•Physical Review A•Dec 10, 2019•18 citations

Electrostatic modes as a diagnostic in Penning trap experiments

Carl S. Weimer, J. J. Bollinger, David J. Wineland +1 more

A subset of electrostatic modes of a cold cloud of electrons trapped in a Penning trap has been observed and identified using a recent theoretical model. The detection of these modes is accomplished using electronic techniques which could apply to any ion species. The modes are observed in the low density, low rotation limit of the cloud where the electrons approach a two-dimensional charged disk. We observe both axially symmetric and asymmetric drumhead modes. By measuring the frequency of these modes the shape, rotation frequency, and density of the cloud is found in a real-time non-destructive manner. In addition, it is found that radio-frequency sideband cooling compresses the cloud increasing its density. The ability to measure and control the density of a trapped ion cloud might be useful for experiments on low-temperature ion/neutral collisions or recombination rates.

Bulletin of the American Physical Society•May 1, 1993•0 citations
The microwave-cavity mode pattern has been directly observed in an old-style compensated Penning trap by a simple bolometric technique which monitors changes in the temperature of the axial center-of-mass motion for a cloud of electrons. The method allows one to easily determine the position of individual modes to a precision better than 0.01%. Presently, over 60 modes have been observed for fields between 17 and 60 kG and an upper limit estimate of 2300 has been made for the cavity Q.
Electronic feedback is used to self-excite the axial oscillation of a single electron in a Penning trap. Large, stable, easily detected oscillations arise even in an anharmonic potential. Amplitudes are controlled by adjusting the feedback gain, and frequencies can be made nearly independent of amplitude fluctuations. Quantum jump spectroscopy of a perpendicular cyclotron motion reveals the absolute temperature and amplitude of the self-excited oscillation. The possibility to quickly measure parts per billion frequency shifts could open the way to improved measurements of e(-), e(+), p, and (-)p magnetic moments.
With a superposition of static electric and magnetic fields, a Penning trap can confine a single electron indefinitely. A weak coupling of the electron to its environment makes the system ideal for precision measurements but renders detection of the electron’s motion difficult. In order to measure fundamental properties of an electron, we employ a Penning trap cooled by a dilution refrigerator. This experimental setup requires extremely low-noise and low-power cryogenic amplifiers for detection of the electron’s axial motion. We design and demonstrate new amplifiers, resulting in a significant decrease of the axial temperature and in an improved signal to noise ratio. We use feedback to cool the axial motion and to self-excite the axial motion for continuous monitoring of the axial frequency. These techniques for cooling and measuring the axial frequency may contribute to an improved measurement of the electron g factor, a more stringent CPT test in leptons, and a more precise measurement of the proton-electron mass ratio.
In this paper, the dynamics of an unbalanced two-ion crystal comprising the ``target'' and the ``sensor'' ions confined in a Penning trap along the magnetic-field axis has been studied. First, the low amplitude regime is addressed. In this regime, the overall potential including the Coulomb repulsion between the ions can be considered harmonic and the axial, magnetron, and reduced-cyclotron modes split up into the so-called stretch and common modes, that are generalizations of the well-known ``breathing'' and ``center-of-mass'' motions of a balanced crystal made of two ions. By using optical detection to measure the frequencies of the modes of the crystal, and of the sensor ion on its own, in the quantum regime of motion, it will be possible to determine the target ion's free-cyclotron frequency. The nonharmonicity of the Coulomb interaction is also discussed since this causes large systematic effects, which are minimized due to the high sensitivity of the optical detection method when the crystal is cooled to the ground state of motion in the Penning trap.
A subset of electrostatic modes of a cold cloud of electrons trapped in a Penning trap has been observed and identified using a recent theoretical model. The detection of these modes is accomplished using electronic techniques which could apply to any ion species. The modes are observed in the low density, low rotation limit of the cloud where the electrons approach a two-dimensional charged disk. We observe both axially symmetric and asymmetric drumhead modes. By measuring the frequency of these modes the shape, rotation frequency, and density of the cloud is found in a real-time non-destructive manner. In addition, it is found that radio-frequency sideband cooling compresses the cloud increasing its density. The ability to measure and control the density of a trapped ion cloud might be useful for experiments on low-temperature ion/neutral collisions or recombination rates.