Analysis of thermal radiation in ion traps for optical frequency standards

Abstract

In many of the high-precision optical frequency standards with trapped atoms or ions that are under development to date, the AC Stark shift induced by thermal radiation leads to a major contribution to the systematic uncertainty. We present an analysis of the inhomogeneous thermal environment experienced by ions in various types of ion traps. Finite element models which allow the determination of the temperature of the trap structure and the temperature of the radiation were developed for 5 ion trap designs, including operational traps at PTB and NPL and further optimized designs. Models were refined based on comparison with infrared camera measurement until an agreement of better than 10% of the measured temperature rise at critical test points was reached. The effective temperature rises of the radiation seen by the ion range from 0.8 K to 2.1 K at standard working conditions. The corresponding fractional frequency shift uncertainties resulting from the uncertainty in temperature are in the 10-18 range for optical clocks based on the Sr+ and Yb+ E2 transitions, and even lower for Yb+ E3, In+ and Al+. Issues critical for heating of the trap structure and its predictability were identified and design recommendations developed.

arXiv comment16 pages, submitted to Metrologia

References in corpus (12)

• An Optical Lattice Clock with Accuracy and Stability at the $10^{-18}$ Level
• Frequency Comparison of Two High-Accuracy Al+ Optical Clocks
• Systematic evaluation of an atomic clock at 2e-18 total uncertainty
• Frequency ratio of two optical clock transitions in ${}^{171}$Yb${}^{+}$ and constraints on the time-variation of fundamental constants
• Multipolar theory of black-body radiation shift of atomic energy levels and its implications for optical lattice clocks
• High-accuracy optical clock based on the octupole transition in 171Yb+
• High accuracy correction of blackbody radiation shift in an optical lattice clock
• An atomic clock with $1\times 10^{-18}$ room-temperature blackbody Stark uncertainty
• Precision calculation of blackbody radiation shifts for optical frequency metrology
• Linear Paul trap design for an optical clock with Coulomb crystals
• A high-precision rf trap with minimized micromotion for an In+ multiple-ion clock
• A Cs-Based Optical Frequency Measurement Using Cross-Linked Optical and Microwave Oscillators

Cited by in corpus (26)

• Single-Ion Atomic Clock with $3\times 10^{-18}$ Systematic Uncertainty
• Highly charged ions: optical clocks and applications in fundamental physics
• Optical clock comparison test of Lorentz symmetry
• Atomic Clocks for Geodesy
• A transportable 40Ca+ single-ion clock with $7.7\times 10^{-17}$ systematic uncertainty
• Controlling systematic frequency uncertainties at the $10^{-19}$ level in linear Coulomb crystals
• Search for ultralight dark matter from long-term frequency comparisons of optical and microwave atomic clocks
• Towards a Transportable Aluminium Ion Quantum Logic Optical Clock
• A cryogenic radio-frequency ion trap for quantum logic spectroscopy of highly charged ions
• The unit of time: present and future directions
• A Single-Ion Trap with Minimized Ion-Environment Interactions
• Experimental and theoretical investigation of a multi-mode cooling scheme using multiple EIT resonances
• Evaluation of trap-induced systematic frequency shifts for a multi-ion optical clock at the $10^{-19}$ level
• Evaluation of a ${}^{88}$Sr${}^{+}$ optical clock with a direct measurement of the blackbody radiation shift and determination of the clock frequency
• The collisional frequency shift of a trapped-ion optical clock
• Coherent excitation of the highly forbidden electric octupole transition in ${}^{172}$Yb${}^{+}$
• Trapping, Shaping and Isolating of Ion Coulomb Crystals via State-selective Optical Potentials
• Prospects of a Pb${}^{2+}$ ion clock
• High-Accuracy Determination of Paul-Trap Stability Parameters for Electric-Quadrupole-Shift Prediction
• Sub-kelvin temperature management in ion traps for optical clocks
• Evaluation of the blackbody radiation shift of an Yb optical lattice clock at KRISS
• Evaluation of blackbody radiation shift with temperature associated fractional uncertainty at 10E-18 level for 40Ca+ ion optical clock
• A scheme for quantum-logic based transfer of accuracy in polarizability measurement for trapped ions using a moving optical lattice
• Ion trap with gold-plated alumina: substrate and surface characterization
• Test and characterization of multilayer ion traps on fused silica
• Endcap-Type Paul Trap for Precision Spectroscopy and Studies of Controlled Interactions