Hyperfine structure measurements in metastable states of165Ho

Abstract

The hyperfine structure constants and the electronic gj factor of the state 4f 11 6s 2 4111/2 belonging to the holmium ground multiplet have been measured using the atomic beam magnetic resonance technique combined with a state-selective laser-induced detection of the resonant atoms. By the same method the gj factor of the level 4f t~ 6s2419/2 was determined, while the hyperfine structures of this metastable state and of two high-lying even parity states have been investigated by high resolution laser spectroscopy. The results for the experimental A and B factors of all four members of the ground multiplet allow a least-squares evaluation of the three magnetic dipole and the three electric quadrupole effective radial parameters for the configuration 4f la 6s 2 of holmium, yielding an accurate value for the spectroscopic nuclear electric quadrupole moment: Qhfs(~6SHo)=2.716(9)b (uncorrected for quadrupole shielding). From a comparison to the quadrupole moments measured in mesic holmium atoms the shielding factor could be estimated. Experimental MethodWhile the holmium energy spectrum comprises several low-lying fine structure states arising from the The atomic beam was evaporated crucible-free from a cylindrical holmium target by electron impact from a 100kV electron gun. This universal evaporation method [-7, 8], originally designed for the highly refractive 4d-and 5d-elements, was used because it allows an enhancement of the population of the metastable states by the decay of electron bombardment excited high-lying fine structure levels.Since the melting point of holmium is only 1,740 K the electron gun was run at a low emission current of 1.5 mA to produce the atomic beam at a vapour pressure of about 0.1 mm Hg. The atoms then pass conventionally equipped flop-in type ABMR magnetic field regions and are focussed on the detector slit if they have undergone an rf transition in the Cfield. The precisely known 39K hfs transitions of a simultaneously running potassium beam which emerges from a resistance heated oven and is registrated by a hot-wire detector are used for a regulation system [9] continuously controlling the magnetic field strength in the C-region of the apparatus. Behind the detector slit the rf-resonant holmium atoms are crossed at right angle by the beam 0340-2193/82/0307/0193/$01.60

Measurement of holmium Rydberg series through magneto-optical trap depletion spectroscopy

“…[27]. This gives an energy of 24360.790(1) cm −1 , which is combined with precise measurements of the ground [28,29] and excited state [25] hyperfine splittings to yield an absolute frequency of the MOT laser given by 730.31682(3) THz. This value is used to calibrate the wavemeter that measure the frequency of the scanned 413 nm Rydberg laser, resulting in a total uncertainty of 200 MHz or 0.007 cm −1 in the absolute energy of the measured levels.…”

Scaling the neutral-atom Rydberg gate quantum computer by collective encoding in holmium atoms

“…The hyperfine constants of the ground state multiplets are known with high accuracy [29,30] leading to the splittings shown in Fig. 4.…”

“…The qubit phase is sensitive to magnetic fields since the g F Landé factors are different for all F levels. The values indicated in the figure assume L − S coupling and no configuration mixing, which is an accurate description for the ground state multiplet [30]. A stable magnetic environment is therefore necessary to prevent qubit dephasing.…”

“…Using σ + polarized light and including repumping frequencies to depopulate all hyperfine levels with F < 11 will result in initialization of all atoms into the reservoir state |s = |11, 11 . The Ho ground state has vanishing configurational mixing with other levels [30] so the limiting factor as regards the efficacy of state preparation will be due to mixing of the upper state of the transition used for pumping, as well as Raman transitions into lower hyperfine states. As mentioned above, one approach to maximizing the state purity is to shelve the |s state in an excited metastable level of the ground electronic configuration using transitions s 1 , s 2 in Fig.…”

Radio-frequency spectroscopy in the states3 D 3,2 of platinum

“…Therefore, further rf measurements of the hfs in the configurations 5dS6s 2 and 5d96s of platinum are very desirable. Such ABMR investigations can be performed by applying a state-and isotope-selective laser detection system [15,16]. In Table 5 the experimental (r -3) values are compared with relativistic self-consistent-field calculations which have been performed by Biittgenbach [10] using the multi-configuration Dirac-Fock method (MCDF) [17] and by Olsson and Rosen [18] using the optimized Hartree-Fock-Slater (OHFS) method.…”