Related papers: Additional clock transitions in neutral ytterbium …
Strongly interacting quantum many-body systems are fundamentally compelling and ubiquitous in science. However, their complexity generally prevents exact solutions of their dynamics. Precisely engineered ultracold atomic gases are emerging…
The hyperfine constants of the $^3$P$^{\circ}_2$ state in neutral Yb have been measured using three different dipole transitions. This state was recently shown to have a comparatively large hyperfine magnetic octupole splitting, and thus a…
We report on the observation of the $4f^{14}6s^{2}~^1S_0- 4f^{13}5d6s^{2}(J=2)$ transition at 431 nm in $^{171}$Yb by depleting atoms in a magneto-optical trap formed by the $6s^{2}~^1S_0-6s6p~^3P_1$ intercombination transition. The…
We report a frequency measurement of the 1S0-3P0 transition of 87Sr atoms in an optical lattice clock. The frequency is determined to be 429 228 004 229 879 (5) Hz with a fractional uncertainty that is comparable to state-of-the-art optical…
We use frequency comb-based optical two-way time-frequency transfer (O-TWTFT) to measure the optical frequency ratio of state-of-the-art ytterbium and strontium optical atomic clocks separated by a 1.5 km open-air link. Our free-space…
Although Niobium is a well characterized material it still shows some anomalies that are not yet understood. Therefore we revisit its metastable phases using density functional theory. First, we systematically compare energies and ground…
We present the experimental demonstration of non-destructive probing of the 1S0-3P0 clock transition probability in an optical lattice clock with 87Sr atoms. It is based on the phase shift induced by the atoms on a weak off-resonant laser…
Laser spectroscopy of the low lying $^1$P and $^3$D states in atomic barium has been performed. This work contributes substantially to the development of an effective laser cooling and trapping for heavy alkaline earth elements and aims in…
Hyperfine-induced electric dipole contributions may significantly increase probabilities of otherwise very weak electric octupole and magnetic quadrupole atomic clock transitions (e.g. transitions between $s$ and $f$ electron orbitals).…
We present a detailed description of experimental studies of the parity violation effect in an isotopic chain of atomic ytterbium (Yb), whose results were reported in a recent Letter [Antypas et al., Nat. Phys. 15, 120 (2019)]. We discuss…
In this work, the $4D_{3/2}|3,\pm2\rangle \rightarrow 4D_{5/2}|3,\pm2\rangle$ transition in the Nb$^{4+}$ ion is identified as a promising candidate for a terahertz (THz) atomic clock, with the transition frequency occurring at 56.0224 THz.…
Quadrupole shifts for three prominent clock transitions, $[4f^{14} 6s] ^2S_{1/2} \rightarrow [4f^{14} 5d] ^2D_{3/2}$, $[4f^{14} 6s] ^2S_{1/2} \rightarrow [4f^{14} 5d] ^2D_{5/2}$ and $[4f^{14} 6s] ^2S_{1/2} \rightarrow [4f^{13} 6s^2]…
Optical precision spectroscopy of isotope shifts can be used to test for new forces beyond the Standard Model, and to determine basic properties of atomic nuclei. We measure isotope shifts on the highly forbidden ${}^2S_{1/2} \rightarrow…
In one-dimensional random walks, the waiting time for each direction transitions is the same, even in the presence of bias, as a consequence of the microscopic-reversibility. We study the symmetry breaking of forward/ backward transition…
We experimentally investigate an optical frequency standard based on the 467 nm (642 THz) electric-octupole reference transition 2S1/2(F=0) -> F7/2(F=3) in a single trapped 171Yb+ ion. The extraordinary features of this transition result…
The advent of novel measurement instrumentation can lead to paradigm shifts in scientific research. Optical atomic clocks, due to their unprecedented stability and uncertainty, are already being used to test physical theories and herald a…
We compare two optical clocks based on the $^2$S$_{1/2}(F=0)\to {}^2$D$_{3/2}(F=2)$ electric quadrupole (E2) and the $^2$S$_{1/2}(F=0)\to {}^2$F$_{7/2}(F=3)$ electric octupole (E3) transition of $^{171}$Yb$^{+}$ and measure the frequency…
We propose an optical clock based on narrow, spin-forbidden M1 and E2 transitions in laser-cooled neutral titanium. These transitions exhibit much smaller black body radiation shifts than those in alkaline earth atoms, small quadratic…
We study metastability and nucleation for the Blume-Capel model: a ferromagnetic nearest neighbour two-dimensional lattice system with spin variables taking values in -1,0,+1. We consider large but finite volume, small fixed magnetic field…
Optical lattice clocks surpass primary Cs microwave clocks in frequency stability and accuracy, and are promising candidates for a redefinition of the second in the International System of Units (SI). However, the robustness of optical…