Microscopic origin of anomalous motional heating in ion traps · revision history
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Accepted · first revision · record
- Title
- Microscopic origin of anomalous motional heating in ion traps
- Plain
- Ions held above metal electrodes heat up far faster than the electrical noise of the metal predicts, which spoils the shared motion that ion-qubit gates use. Which surface process produces this excess electric-field noise is not established.
- Precise
- Trapped ions at ion-electrode distance $d$ and secular frequency $\omega$ show electric-field noise spectral density $S_E(\omega)$ orders of magnitude above the Johnson-noise value, with approximate power laws $S_E \sim \omega^{-a} d^{-b}$ ($b$ reported roughly between 2 and 4), strong dependence on electrode temperature and large reductions after surface cleaning (exponents approximate). Identify the dominant microscopic mechanism (fluctuating adsorbate dipoles, two-level fluctuators in surface layers, patch-potential diffusion or other) and give a model that predicts $S_E$ as a function of $d$, $\omega$, $T$ and surface preparation.
- Settled by
- A model that predicts measured $S_{E}(\omega, d, T)$ across traps of different materials and surface treatments, confirmed by surface-science characterization of the same electrodes.
- Kind
- phenomenon
- Answer type
- mechanism
- References
- (empty)
- Literature status
- open
- Status note
- Surface cleaning and cryogenic operation lower the noise by orders of magnitude, but no single mechanism accounts for all data (review: Brownnutt, Kumph, Rabl and Blatt, Rev. Mod. Phys. 87, 1419, 2015, arXiv:1409.6572).
- Posed since
- (empty)