Microscopic model of electric-field-noise heating in ion traps

Journal Article · Mon Aug 15 04:00:00 EDT 2011 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.84.023412· OSTI ID:22075492

Safavi-Naini, A ^[1]; Rabl, P ^[2]; Weck, P F ^[3]; Sadeghpour, H R ^[4]

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1. Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
2. Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck (Austria)
3. Department of Chemistry and Harry Reid Center, University of Nevada, Las Vegas, Nevada 89154 (United States)
4. ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138 (United States)

Motional heating of ions in microfabricated traps is one of the open challenges hindering experimental realizations of large-scale quantum processing devices. Recently, a series of measurements of the heating rates in surface-electrode ion traps characterized their frequency, distance, and temperature dependencies, but our understanding of the microscopic origin of this noise remains incomplete. In this work we develop a theoretical model for the electric field noise which is associated with a random distribution of adsorbed atoms on the trap electrode surface. By using first-principles calculations of the fluctuating dipole moments of the adsorbed atoms we evaluate the distance, frequency, and temperature dependence of the resulting electric field fluctuation spectrum. Our theory reproduces correctly the d{sup -4} dependence with distance of the ion from the electrode surface and calculates the noise spectrum beyond the standard scenario of two-level fluctuators by incorporating all the relevant vibrational states. Our model predicts a regime of 1/f noise which commences at roughly the frequency of the fundamental phonon transition rate and a thermally activated noise spectrum which for higher temperatures exhibits a crossover as a function of frequency.

• OSTI ID: 22075492
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 2 Vol. 84; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
ATOMS
DIPOLE MOMENTS
ELECTRIC FIELDS
ELECTRODES
FLUCTUATIONS
FREQUENCY DEPENDENCE
HEATING
NOISE
PHONONS
SPECTRA
TEMPERATURE DEPENDENCE
TRAPS
VIBRATIONAL STATES