We show that three group IIIB divalent ions, B+, Al+, and In+, have anomalously small blackbody radiation (BBR) shifts of the ns^2 1S0 - nsnp 3P0 clock transitions. The fractional BBR shifts for these ions are at least 10 times smaller than those of any other present or proposed optical frequency standards at the same temperature, and are less than 0.3% of the Sr clock shift. We have developed a hybrid configuration interaction + coupled-cluster method that provides accurate treatment of correlation corrections in such ions, considers all relevant states in the same systematic way, and yields a rigorous upper bound on the uncertainty of the final results. We reduce the BBR contribution to the fractional frequency uncertainty of the Al+ clock to 4 \times 10^{-19} at T=300K. We also reduce the uncertainties due to this effect at room temperature to 10^{-18} level for B+ and In+ to facilitate further development of these systems for metrology and quantum sensing. These uncertainties approach recent estimates of the feasible precision of currently proposed optical atomic clocks.
High accuracy correction of blackbody radiation shift in an optical lattice clock
我们已经确定了黑体辐射在锶中的$5s^2$ $^1$ S $_0$ -- $5s5p$ $^3$ P $_0$时钟跃迁上引起的频移。以前它的不确定性限制了锶晶格钟的不确定性为$1\times10^{-16}$。现在，与黑体辐射位移校正相关的不确定性转化为室温下的$5\times 10^{-18}$相对频率不确定性。我们的评估是基于两个时钟状态的差分直流极化率的测量和使用此值和其他原子属性的实验数据的动态贡献的建模。
Precision measurements of quantum systems often seek to probe or must account for the interaction with blackbody radiation. Over the past several decades, much attention has been given to AC Stark shifts and stimulated state transfer. For a blackbody in thermodynamic equilibrium, these two effects are determined by the expectation value of photon number in each mode of the Planck spectrum. Here, we explore how the photon number variance of an equilibrium blackbody generally leads to a parametric broadening of the energy levels of quantum systems that is inversely proportional to the square-roo…
We report experimental measurements of the rates of blackbody radiation-induced transitions between high-lying (n>60) S, P and D Rydberg levels of rubidium atoms in a magneto-optical trap using a hybrid field ionization and state-selective depumping technique. Our results reveal significant deviations of the measured transition rates from theory for well-defined ranges of the principal quantum number. We assume that the most likely cause for those deviations is a modified blackbody spectrum inside the glass cell in which the magneto-optical trap is formed, and we test this assumption by instal…
An ensemble of excited atoms can synchronize emission of light collectively in a process known as superradiance when its characteristic size is smaller than the wavelength of emitted photons. The underlying superradiance depends strongly on electromagnetic (photon) fields surrounding the atomic ensemble. High mode densities of microwave photons from $300\,$K blackbody radiation (BBR) significantly enhance decay rates of Rydberg states to neighbouring states, enabling superradiance that is not possible with bare vacuum induced spontaneous decay. Here we report observations of the superradiance …
Blackbody radiation (BBR) sources are calculable radiation sources that are frequently used in radiometry, temperature dissemination, and remote sensing. Despite their ubiquity, blackbody sources and radiometers have a plethora of systematics. We envision a new, primary route to measuring blackbody radiation using ensembles of polarizable quantum systems, such as Rydberg atoms and diatomic molecules. Quantum measurements with these exquisite electric field sensors could enable active feedback, improved design, and, ultimately, lower radiometric and thermal uncertainties of blackbody standards.…
Access via laboratory experiments to the level mixing effect induced by blackbody radiation and its influence on the cosmological hydrogen recombination problem
As optical clocks are improved to reach the frequency uncertainty below the 10$^{-17}$ level, the frequency shift due to the blackbody radiation (BBR) has been one of the major systematic effects hindering further improvement. To evaluate the BBR shift of an Yb optical lattice clock at KRISS, we installed an in-vacuum BBR shield and made radiation thermometry using a black-coated-sphere thermal probe. After we quantitatively measured the conduction loss of the thermal probe and the effects of all the external radiation sources, we determined the temperature at the atom trap site with an uncert…
Blackbody radiation shift of B$^+$ clock transition
计算B $^+$时钟跃迁的黑体辐射位移。用组态相互作用方法计算了$^+$ $^1$ S $^e$、$2s2p$ $^1$ P $^o$和$2s2p$ $^3$ P $^o$态的极化率.推荐的偶极极化率分别为9.64（3）$a_0^3$、7.78（3）$a_0^3$和16.55（5）$a_0^3$。在300 K下，$2s^2$ $^1$ S $^e$ $\to$ $2s2p$ $^3$ P $^o_0$跃迁的导出频移为0.0160（5）Hz。偶极极化率与较早的相对论计算（Safronova { \em et al.}物理修订版信函{ \bf 107} 143006（2011））至优于0.2%。四极和八极极化率和非绝热多极极化率也报告。
Atom interferometry is amongst the most advanced technologies that provides very high-precision measurements. There can exist a number of obscure forces that can interfere with the atoms used in this instrument. In the present work, we are probing possible roles of one such important forces, known as ``blackbody friction force (BBFF)'', that may affect the precisions in the measurements made using atom interferometers based on the Rb and Cs atoms. The BBFF can be generated on atoms due to the black-body radiations emitted by the stray electromagnetic fields present in the experimental set-up a…
