We observe "trilobitelike" states of ultracold (85)Rb(2) molecules, in which a ground-state atom is bound by the electronic wave function its Rydberg-atom partner. populate these through ultraviolet excitation weakly and access regime trilobitelike at low principal quantum numbers with vibrational turning points around 35 Bohr radii. This demonstrates that, unlike previous studies that used free-to-bound transitions, can also be excited bound-to-bound transitions. approach provides high...

Extending the understanding of Bose-Einstein condensate (BEC) physics to new geometries and topologies has a long varied history in ultracold atomic physics. One such geometry is that bubble, where would be confined surface an ellipsoidal shell. Study this give insight into collective modes, self-interference effects, topology-dependent vortex behavior, dimensionality crossovers from thick thin shells, properties condensates pushed ultradilute limit. Here we propose implement realistic...

We report continuous direct photoassociative formation of ultracold KRb molecules in the lowest vibrational levels $(v"=0 -10)$ electronic ground state $(X ^1\Sigma^+)$, starting from $^{39}$K and $^{85}$Rb atoms a magneto-optical trap. The process exploits newfound resonant coupling between $2(1), v'=165$ $4(1), v'=61$ levels, which exhibit an almost equal admixture uncoupled eigenstates. production rate $X^1\Sigma^+$ ($v"$=0) level is estimated to be $5\times10^3$ molecules/sec.

Promising pathways for photoassociative formation of ultracold heteronuclear alkali metal dimers in their lowest rovibronic levels (denoted X(0,0)) are examined using high-quality ab initio calculations potential energy curves currently available. A promising pathway KRb, involving the resonant coupling 2(1)Pi and 1(1)Pi states just below excited asymptote (K(4s) + Rb(5p(1/2))), is found to occur also RbCs less promisingly KCs also. The 3(1)Sigma(+) states, asymptote, be LiNa, LiK, LiRb LiCs...

We report on the observation of blue-detuned photoassociation in Rb(2), which vibrational levels are energetically above corresponding excited atomic asymptote. (85)Rb atoms a MOT were photoassociated at short internuclear distance to 1(3)Π(g) state rate approximately 5 × 10(4) molecules s(-1). have observed most predicted for all four spin-orbit components; 0(+)(g), 0(-)(g), 1(g), and 2(g), including 0(+)(g) outer well. These decay metastable a(3)Σ(+)(u) state, some preferentially v'' = 0...

Molecular vibrational transitions are prime candidates for model-independent searches variation of the proton-to-electron mass ratio. Searches present-day achieve highest sensitivity with deep molecular potentials. We identify several high-sensitivity in deeply bound ${\mathrm{O}}_{2}{}^{+}$ ion. These electric-dipole forbidden and have narrow linewidths. The most sensitive take advantage an accidental degeneracy between states different electronic suggest experimentally feasible routes to a...

Vibrational overtones in deeply-bound molecules are sensitive probes for variation of the proton-to-electron mass ratio μ . In nonpolar molecules, these may be driven as two-photon transitions. Here, we present procedures experiments with 16 O 2 + , including state-preparation through photoionization, a probe, and detection. We calculate transition dipole moments between all X Π g vibrational levels those A u excited electronic state. Using moments, rates AC-Stark-shift systematics...

The high-resolution rovibronic spectroscopies of cold and ultracold molecules (e.g. supersonic molecular beam excitation spectra (MB), photoassociation atoms (PA), resonance-enhanced multiphoton ionization (REMPI), stimulated Raman transfer (SRT) spectra) are major current interest. This manuscript summarizes the significant level understanding these various spectroscopies, enabled by using simple graphical semiclassical ideas shortcuts. Physical realizations will be illustrated alkali metal...

We report the observation of photoassociation to $2{\phantom{\rule{0.16em}{0ex}}}^{1}\phantom{\rule{-0.16em}{0ex}}{\ensuremath{\Sigma}}_{g}^{+}$ state ${}^{85}$Rb${}_{2}$. have observed two vibrational levels (${v}^{\ensuremath{'}}=98,99$) below $5{s}_{1/2}+5{p}_{1/2}$ atomic limit and 11 (${v}^{\ensuremath{'}}=102$--112) above it. The photoassociation---and subsequent spontaneous emission---occur predominantly between 15 20 bohrs in a region internuclear distance best described as...

We report an upper bound to the ionization energy of 85Rb2 31348.0(6) cm-1, which also provides a lower dissociation D0 85Rb2+ 6307.5(6) cm-1. These bounds were measured by onset autoionization excited states below 5s+7p atomic limit. form molecules via photoassociation ultracold 85Rb atoms, and subsequently excite single-photon ultraviolet transitions above threshold.

We generate coherent ultraviolet radiation at 313 nm as the third harmonic of an external-cavity diode laser. use this for laser cooling trapped beryllium atomic ions and sympathetic co-trapped beryllium-hydride molecular ions. An LBO crystal in enhancement cavity generates second harmonic, a BBO doubly resonant mixes with fundamental to produce harmonic. Each is preceded by tapered amplifier increase light. The 36-mW output power all-semiconductor-gain system will enable quantum control...

Ultracold photoassociation is typically performed at large internuclear separations, where the scattering wavefunction amplitude and Franck–Condon overlap maximized. Recently, work by this group others on alkali-metal diatomics has shown that can efficiently form molecules short distance in both homonuclear heteronuclear dimers. We propose short-range due to excitation near maximum inner wall of lowest triplet potential. show factors (FCFs) from highest-energy bound state almost precisely...

We report the observation and analysis of 3 3ΠΩ double-minimum electronic excited state 39K85Rb. The spin-orbit components (0+, 0−, 1, 2) this are investigated based on potentials developed from available ab initio potential curves. have assigned vibrational levels v′ = 2–11 3Π1,2 2–12 \documentclass[12pt]{minimal}\begin{document}$3\,^3\Pi _{0^{+/-}}$\end{document}3Π0+/−3 potential. compare our experimental observations with predictions theoretical potentials. resonance enhanced multiphoton...

We report new results on the spectroscopy of 3 (3)Σ(+) electronic state (39)K(85)Rb. The observations are based resonance-enhanced multiphoton ionization ultracold KRb molecules starting in vibrational levels v'' = 18-23 a and ionized via intermediate state. a-state formed by photoassociation (39)K (85)Rb atoms to 3(0(+)) followed spontaneous emission. discuss potential applications this future experiments, as pathway for populating lowest well X

Rydberg molecules, often exemplified by long-range ``trilobite'' are a subject of much recent interest at high principal quantum number $n$. States that use the same bonding mechanism can exist lower $n$ and less-extreme internuclear separations still quite long range. We high-resolution pulsed amplifier to study previously detected transitions low-$n$ molecular state near $5s+7p$ asymptote in $^{85}\mathrm{Rb}_{2}$. The observed line structure is modeled using precise ground-state positions...

We report on the anomalously high line strength of a single rotational level in ultracold photoassociation two 85Rb atoms to form 85Rb2. The v' = 111, J' 5 belongs Hund's case (c) 2 (0g+) state, which correlates (a) 1 \Sigma g+ state. Its is caused by coupling with very near-resonant long-range component energetically degenerate 155, (1g)$ correlating \Pi g enhanced an order magnitude through this coupling, relative nearby vibrational levels and even same level. This enhancement addition...

Vibrational overtones in deeply bound molecules are sensitive probes for variation of the proton-to-electron mass ratio μ. In nonpolar molecules, these may be driven as two-photon transitions. Here, we present procedures experiments with O2+, including state-preparation through photoionization, a two-photon probe, and detection. We calculate transition dipole moments between all X2Пg vibrational levels those A2Пu excited electronic state. Using moments,...