Zeeman effect in the saturation spectroscopy of the 87Rb D2 line
Zeeman splitting of the 5s level of Rb, including fine structure and hyperfine structure splitting. Here F = J + I, where I is the nuclear spin. (for Rb, I = 3/2). Main · Videos; Dating singapore girl name zeeman splitting rubidium 87 dating una semana en corcega online dating una semana en corcega online dating. The shifts of the Zeeman Effect in the small field limit can be obtained with 1st order perturbation Fig 1 line hyperfine structure of Rb (left) and Rb- 87 (right) in no magnetic field shows how the .. Name. Dates of measurements.
The rate of inelastic processes can therefore be controlled by the atomic spin. Remarkable examples include molecular association and three-body recombination close to a magnetic Feshbach resonance 9 Ultracold atom—ion collisions are studied in several laboratories and efforts to gain control over different collisional properties are ongoing 4 — 811 — Precise control over ultracold atom—ion collisions has rich prospects such as emulating solid-state systems 15performing atom—ion entanglement 16quantum gates 17and the formation of mesoscopic ions The research of ultracold atom—ion collisions can also lead to better understanding of interstellar molecular formation In recent experiments, different inelastic collision rates were shown to depend on the collision energy as well as the electronic state of an atom—ion system 5 — 8.
However, no spin control of different collisional properties was demonstrated to date. Although the spin of both ultracold atoms and ions can be prepared in a precise predetermined state, for this initial spin state to control a collisional process, the total spin of the system has to be conserved during the collision.
Thus, spin dynamics during the collision has to be dominated by spin exchange and the relaxation of spin through, e. Spin exchange induced spin locking, and collective spin excitation were observed in BEC 22 and non-degenerate gases Spin-exchange collisions between noble gases and alkali atoms were used to polarize the nuclear spin of the noble-gas atoms We find that spin dynamics during a collision is dominated by spin exchange and spin relaxation is largely suppressed.
By preparing the atoms in different initial spin states, we demonstrate control over two inelastic collision rates. First, we can turn spin exchange off and on by preparing the ion spin parallel or antiparallel to that of the surrounding atomic cloud. This paper demonstrates our suc- by allowing one element to act as a collocated detector cess at producing continuous and overlapped slow beams for a second quantum gas a thermometer in Ref.
In other cases, the gaseous designed Zeeman slower and two-elements oven. Mix- tures of elements with a large mass ratio are of particular We summarize the operating principle and some de- interest for studying novel superfluid properties such as sign considerations of an increasing-field Zeeman slower spin impurities , breached pair superfluids [17, 18], to highlight the requirements for slowing multiple ele- and crystalline superfluid phases .
Quantum gas mix- ments and to describe our strategy to satisfy these re- tures also serve as a precursor for the formation of ul- quirements [26, 28, 29]. Atoms in a Zeeman slower are tracold heteronuclear molecules [14, 20—24]. Molecules decelerated and Doppler cooled by radiation pressure as of atoms with large mass ratios, such as rubidium and they scatter photons out of a laser beam propagating lithium, are predicted to have large dipole moments , counter to the atomic beam.
To maintain this deceler- and may be useful for studies of dipolar quantum gases, ation and cooling with a constant laser frequency, the precision measurements, and quantum computing. Atoms starting with longitudinal tures rapidly, robustly, and efficiently. The adiabaticity require- address: Such a large ratio must be considerd in the slower design to achieve high brightness of both elements.
The box in b emphasizes atom upon entering the slower. This transverse heat- the key concept of our slower: Transverse heating is more severe for lithium than rubidium because of its lighter mass higher vr and larger initial velocity . The key con- three-stage slower based on the desired length of each cept of our design stems from the realization that the stage and a constant deceleration within the adiabaticity detrimental effects of transverse heating on the lighter limit for the appropriate atom.
The design parameters lithium beam are most severe when the lithium beam is are listed in Table II. The optimized winding was deter- slow, requiring that the final stage of slowing the lithium mined numerically by gradient descent on a cost function beam be performed close to the maximum deceleration, taking into account the deviation from the target field, at high magnetic field gradient, and in close proximity to the adiabaticity requirement, the rubidium diabaticity the magneto-optical trap.
In contrast, a faster lithium requirement in Stage III, and the peak field value. To beam can be slowed without a great decrease in beam produce the precise field demanded by such aggressive brightness at a lower deceleration and magnetic field gra- design parameters, the optimization allowed for 16 layers dient appropriate for the heavier element, rubidium. The opti- other words, our strategy is to reduce the time of flight of mization method varied the current through each stage lithium in a slower long enough to decelerate a significant independently with fixed physical boundaries between fraction of the rubidium thermal distribution.
Thus, we each stage. The measured magnetic field of Stage II matches well The nozzle directs collimated beams of rubidium and with the calculated field for a perfectly wound coil. The lithium through the oven chamber Fig. A shut- measured rms deviation of the magnetic field is only ter can rotate to block the beams. A gate valve seals 0. Glass viewports before and after a differential pumping stage provide optical access, allowing for trans- verse optical pumping of the atomic beams.
Atoms not cap- separate reservoirs for rubidium and lithium, inspired by tured stick to a cold in-vacuum gold mirror that reflects Ref.
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A single-reservoir design is impractical for the the Zeeman slower laser onto the atomic beam axis. The rubidium-lithium mixture owing to the vastly different mirror allows the laser light to enter the vacuum chamber vapor pressures of the two metals. At the typical lithium through a glass viewport that is not directly exposed to reservoir operating temperature, the equilibrium vapor the atomic beam, preventing its occlusion and corrosion.
The pressure in both chambers termediate nozzle. The higher temperature lithium reser- is dominated by hydrogen.
Spin-controlled atom–ion chemistry
The oven chamber is pumped voir also serves as the mixing chamber. Rubid- kali vapor by a water-cooled chevron baffle.
Differential ium metal is introduced into its reservoir in a sealed glass pumping between the oven and MOT chamber is main- ampoule that is broken after baking out the sealed vac- tained through a thin tube with a hydrogen conductance uum chamber. Lithium metal is cleaned and then added of 1. The Zeeman directly to its reservoir.
The MOT cham- lithium vapor. The beam source is itself a rather specialized apparatus and so we provide more details on its design and performance. The two-element mixing chamber is followed by an We characterize our Zeeman slower by measuring the oven nozzle comprised of a multichannel array of stain- flux of rubidium and lithium with two methods.Atomic line evolution to the Hyperfine Paschen Back regime
First, less steel tubes [36, 37]. The short length allows the oven to op- tube, with sensitivity enhanced by lock-in detection. Sec- erate at a high pressure before collisions deteriorate the ond, we measure the MOT loading rate by collecting flu- collimation. Our array is formed by aligning and then oresced trapping light. See text for description. Position is measured from the MOT. The 0 bottom axis is the magnetic field ramp generated in Stage III.
Marker areas are proportional to the beam flux. A comparison of three operating modes of the slower: