Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userSpin State Detection and Manipulation and Parity Violation in a Single Trapped Ion
300
0
0.0
(
0
)
Authors
M Schacht
Ask ChatGPT about the research
No Arabic abstract
Atomic Parity Violation provides the rare opportunity of a low energy window into possible new fundamental processes at very high mass scales normally investigated at large high energy accelerators. Precise measurements on atomic systems are currently the most sensitive probes of many kinds of new physics, and complement high energy experiments. Present atomic experiments are beginning to reach their limits of precision due to either sensitivity, systematics or atomic structure uncertainties. An experiment in a single trapped Barium ion can improve on all of these difficulties. This experiment uses methods to precisely manipulate and detect the spin state of a single ion in order to measure a parity induced splitting of the ground state magnetic sublevels in externally applied laser fields. The same methods can be used to provide precise measurements of more conventional atomic structure parameters.
rate research
Read More
We demonstrate the use of trapped ytterbium ions as quantum bits for quantum information processing. We implement fast, efficient state preparation and state detection of the first-order magnetic field-insensitive hyperfine levels of 171Yb+, with a measured coherence time of 2.5 seconds. The high efficiency and high fidelity of these operations is accomplished through the stabilization and frequency modulation of relevant laser sources.
We study the formation and destabilization of dark states in a single trapped 88Sr+ ion caused by the cooling and repumping laser fields required for Doppler cooling and fluorescence detection of the ion. By numerically solving the time-dependent density matrix equations for the eight-level system consisting of the sublevels of the 5s 2S1/2, 5p 2P1/2, and 4d 2D3/2 states, we analyze the different types of dark states and how to prevent them in order to maximize the scattering rate, which is crucial for both the cooling and the detection of the ion. The influence of the laser linewidths and ion motion on the scattering rate and the dark resonances is studied. The calculations are then compared with experimental results obtained with an endcap ion trap system located at the National Research Council of Canada and found to be in good agreement. The results are applicable also to other alkaline earth ions and isotopes without hyperfine structure.
Single trapped ions are ideal systems in which to test atomic physics at high precision: they are effectively isolated atoms held at rest and largely free from perturbing interactions. This thesis describes several projects developed to study the structure of singly-ionized barium and more fundamental physics. First, we describe a spin-dependent electron-shelving scheme that allows us to perform single ion electron spin resonance experiments in both the ground 6S_{1/2} and metastable 5D_{3/2} states at precision levels of 10^{-5}. We employ this technique to measure the ratio of off-resonant light shifts (or ac-Stark effect) in these states to a precision of 10^{-3} at two different wavelengths. These results constitute a new high precision test of heavy-atom atomic theory. Such experimental tests in Ba+ are in high demand since knowledge of key dipole matrix elements is currently limited to about 5%. Ba+ has recently been the subject of theoretical interest towards a test of atomic parity violation for which knowledge of dipole matrix elements is an important prerequisite. We summarize this parity violation experimental concept and describe new ideas. (continued...)
We discuss the propagation of hydrogen atoms in static electric and magnetic fields in a longitudinal atomic beam spin echo (lABSE) apparatus. There the atoms acquire geometric (Berry) phases that exhibit a new manifestation of parity-(P-)violation in atomic physics. We provide analytical as well as numerical calculations of the behaviour of the metastable 2S states of hydrogen. The conditions for electromagnetic field configurations that allow for adiabatic evolution of the relevant atomic states are investigated. Our results provide the theoretical basis for the discussion of possible measurements of P-violating geometric phases in lABSE experiments.
We provide a comprehensive theoretical framework for describing the dynamics of a single trapped ion interacting with a neutral buffer gas, thus extending our previous studies on buffer-gas cooling of ions beyond the critical mass ratio [B. Holtkemeier et al., Phys. Rev. Lett. 116, 233003 (2016)]. By transforming the collisional processes into a frame, where the ions micromotion is assigned to the buffer gas atoms, our model allows one to investigate the influence of non-homogeneous buffer gas configurations as well as higher multipole orders of the radio-frequency trap in great detail. Depending on the neutral-to-ion mass ratio, three regimes of sympathetic cooling are identified which are characterized by the form of the ions energy distribution in equilibrium. We provide analytic expressions and numerical simulations of the ions energy distribution, spatial profile and cooling rates for these different regimes. Based on these findings, a method for actively decreasing the ions energy by reducing the spatial expansion of the buffer gas arises (Forced Sympathetic Cooling).
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
