We study the guiding of 87 Rb 59D 5/2 Rydberg atoms in a linear, high-gradient, two-wire magnetic guide. Time delayed microwave ionization and ion detection are used to probe the Rydberg atom motion. We observe guiding of Rydberg atoms over a period of 5 ms following excitation. The decay time of the guided atom signal is about five times that of the initial state. We attribute the lifetime increase to an initial phase of l-changing collisions and thermally induced RydbergRydberg transitions. Detailed simulations of Rydberg atom guiding reproduce most experimental observations and offer insight into the internal-state evolution.There has been a recent surge of interest in cold Rydberg atoms in a linear trapping geometry. Such systems present the possibility of creating one-dimensional spin chains by exciting atoms into high-lying Rydberg levels, which interact strongly due to their large dipole moments [1][2][3]. Rydberg crystals, which have been proposed in a frozen atomic gas using the Rydberg excitation blockade effect, may be an interesting application within a linear structure [4]. Entangled Rydberg atoms prepared in a linear guiding geometry could act as a shuttle for quantum information [5,6]. A one-dimensional trap or guide for Rydberg atoms could be used to further these types of research. Cold Rydberg atoms have been experimentally trapped using magnetic [7], electrostatic [8], and light fields [9]. Conservative trapping of Rydberg atoms in magnetic atom guides has been theoretically investigated in [10][11][12]. Theoretical calculations also indicate the possibility of stationary Rydberg atoms confined in magnetic traps and magnetoelectric traps [13][14][15]. These systems would allow one to study Rydberg gases in a one-dimensional geometry. The Rydberg-Rydberg interaction properties in such a system have been theoretically studied in [16]. In the present paper we report the first guiding of Rydberg atoms in a linear magnetic guide.Two parallel wires carrying equal currents guide cold atoms in low magnetic field seeking states along a linear guiding channel located between the guide wires, where the magnetic field approaches zero. Briefly, our 1.5 m long linear guide [17,18] operates with a magnetic field gradient of ∼1.5 kG/cm, which tightly confines a beam of 87 Rb atoms (prepared in the |F = 1, m F = −1 level of the 5S 1/2 ground-state) in the guiding channel. The forward velocity of the guided atoms is adjusted to ≈1 m/s. The ground state atoms have transverse and longitudinal temperatures of T x,y ≈ 400 µK and T z ≈ 1 mK, respectively. An excitation and detection region for Rydberg atoms is located 85 cm down the guide, illustrated in Fig. 1. We use a three-step Rydberg atom excitation process. A pulsed 780 nm beam (duration 10 µs) pumps the atoms from 5S 1/2 |F = 1, m F = −1 to F = 2. A second pulsed 780 nm beam (duration 5 µs) subsequently drives the atoms on the cycling transition into 5P 3/2 F ′ = 3. The atoms are excited from the 5P 3/2 level to the 59D 5/2 Rydberg level with a tunable, cont...

We study cold rubidium Rydberg atoms, initially prepared in state 59D5/2, guided along a two-wire magnetic atom guide. The evolution of the atoms is driven by the combined effects of internal-state transitions and dipole forces acting on the center-of-mass degree of freedom. State-selective field ionization, applied at a variable delay time, is used to investigate the evolution of the internal-state distribution. We observe a broadening of the field ionization spectrum caused by population transfer between Rydberg states. At late times, the distribution of the remaining Rydberg atoms becomes biased toward states with high principal quantum numbers. The population transfer is attributed to thermal transitions and, to a lesser extent, initial state mixing due to Rydberg-Rydberg collisions. Characteristic components in spatially and temporally resolved distributions of the ion signal are interpreted in the context of the underlying physics. The system is simulated with a model in which the centerof-mass dynamics are treated classically, while the internal-state dynamics are treated quantum mechanically. The simulation qualitatively reproduces most experimental findings and provides experimentally inaccessible information.

We study a photoionization method to detect and image a narrow beam of cold atoms traveling along a high-gradient two-wire magnetic guide that is continuously on. Ions are accelerated in a compact acceleration region, directed through a drift region several centimeters in length, and detected using a position-sensitive ion detector. The potentials of several electrodes can be varied to adjust the imaging properties. Using ion trajectory simulations as well as experiments, we study the passage of the ions through the detection system, the magnification of the detection system, and the time-of-flight characteristics.