FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W2099210514> ?p ?o ?g. }

• W2099210514 abstract "This thesis describes experimental work towards developing a trapped ion quantum information processor. An existing ion trap apparatus was capable of trapping and laser-cooling single ions or small ion strings of 40 Ca+, and had been used for studies of quantum jumps and natural lifetime measurements in Ca. This thesis describes improvements in this apparatus, which have allowed the stability and the flexibility of experimental control of the ions to be greatly increased. This enabled experiments to read out the spin state of a single trapped ion, and to load ions with isotope selectivity through photoionization. The optical systems were improved by installation of new lasers, optical reference cavities, and a system of acousto-optic modulators for laser intensity switching and frequency control. The photon counting for fluorescence detection was improved, and a new photon time-of-arrival correlation circuit developed. This has permitted rapid and more sensitive detection of micromotion, and hence cancellation of stray fields in the trap. A study of resonant circuits in the low RF, high voltage (10 MHz, 1 kV) regime was carried out with a view to developing a new RF supply for the Paul trap with reduced noise and increased power. A new supply based on a helical resonator was built and used to trap ions. This technique has reduced noise and will permit higher secular frequencies to be attained in the future. A magnetic field B in the ion trap is used to define a quantization axis, and in one series of experiments was required to be of order 100 G to provide a substantial Zeeman splitting. A set of magnetic field coils to control the size and direction of B is described. The design of these posed some problems owing to an unforseen issue with the vacuum chamber. In short, it is magnetizable and acts to first approximation like a magnetic shield. The field coils had to be sufficiently substantial to produce the desired field at the ion even in the presence of this shielding effect, and dark resonance (and other) spectra with Zeeman splitting were obtained to calibrate the field using the ion as a probe. Finally, the thesis describes the successful loading of the ion trap by laser photoionization from a weak atomic beam. This involved two new lasers at 423 nm and 389 nm. Saturated absorption spectroscopy of neutral calcium is first described, then transverse excitation of an atomic beam in our vacuum chamber is used to identify all the main isotopes of calcium and confirm their abundances in our source (a heated sample of natural calcium). Finally, photoionization is used to load the trap. This has three advantages over electron-impact ionization. By avoiding an electron gun, we avoid charging of insulating patches and subsequent electric field drift as they discharge; the flux in the atomic beam and hence calcium (and other) deposits on the electrodes can be greatly reduced; and most importantly, the photoionization is isotope selective. Evidence is presented which suggests that even with an non-enriched source, the rare isotope 43 Ca can be loaded with reasonable efficiency. This isotope is advantageous for quantum information experiments for several reasons, but chiefly because its ground state hyperfine structure can act as a stable qubit." @default.
• W2099210514 created "2016-06-24" @default.
• W2099210514 creator A5047343272 @default.
• W2099210514 date "2003-01-01" @default.
• W2099210514 modified "2023-09-26" @default.
• W2099210514 title "Stabilization and control in a linear ion trap" @default.
• W2099210514 cites W1456761951 @default.
• W2099210514 cites W1504549545 @default.
• W2099210514 cites W1516333166 @default.
• W2099210514 cites W1517862262 @default.
• W2099210514 cites W152419500 @default.
• W2099210514 cites W1533795104 @default.
• W2099210514 cites W1540681610 @default.
• W2099210514 cites W1584661976 @default.
• W2099210514 cites W1620538313 @default.
• W2099210514 cites W1622305026 @default.
• W2099210514 cites W1642226671 @default.
• W2099210514 cites W1965261159 @default.
• W2099210514 cites W1965378868 @default.
• W2099210514 cites W1966071962 @default.
• W2099210514 cites W1966533239 @default.
• W2099210514 cites W1966590498 @default.
• W2099210514 cites W1967057824 @default.
• W2099210514 cites W1967742120 @default.
• W2099210514 cites W1967767939 @default.
• W2099210514 cites W1967909467 @default.
• W2099210514 cites W1969840935 @default.
• W2099210514 cites W1971657919 @default.
• W2099210514 cites W1972779143 @default.
• W2099210514 cites W1973676398 @default.
• W2099210514 cites W1974290457 @default.
• W2099210514 cites W1974735444 @default.
• W2099210514 cites W1976894839 @default.
• W2099210514 cites W1978799754 @default.
• W2099210514 cites W1980856895 @default.
• W2099210514 cites W1986718451 @default.
• W2099210514 cites W1987551259 @default.
• W2099210514 cites W1990589285 @default.
• W2099210514 cites W1992370635 @default.
• W2099210514 cites W1992708532 @default.
• W2099210514 cites W1995091322 @default.
• W2099210514 cites W1999450843 @default.
• W2099210514 cites W2000609161 @default.
• W2099210514 cites W2001133809 @default.
• W2099210514 cites W2002372750 @default.
• W2099210514 cites W2008274425 @default.
• W2099210514 cites W2012054446 @default.
• W2099210514 cites W2012206667 @default.
• W2099210514 cites W2013001284 @default.
• W2099210514 cites W2015361431 @default.
• W2099210514 cites W2016005409 @default.
• W2099210514 cites W2017249488 @default.
• W2099210514 cites W2019546904 @default.
• W2099210514 cites W2022204719 @default.
• W2099210514 cites W2023142346 @default.
• W2099210514 cites W2023570296 @default.
• W2099210514 cites W2026402424 @default.
• W2099210514 cites W2032254989 @default.
• W2099210514 cites W2035693295 @default.
• W2099210514 cites W2037232648 @default.
• W2099210514 cites W2037347712 @default.
• W2099210514 cites W2039343706 @default.
• W2099210514 cites W2040057646 @default.
• W2099210514 cites W2042474962 @default.
• W2099210514 cites W2045748092 @default.
• W2099210514 cites W2046802345 @default.
• W2099210514 cites W2048220984 @default.
• W2099210514 cites W2048493999 @default.
• W2099210514 cites W2050334794 @default.
• W2099210514 cites W2052797266 @default.
• W2099210514 cites W2053543037 @default.
• W2099210514 cites W2054090110 @default.
• W2099210514 cites W2054507353 @default.
• W2099210514 cites W2055147397 @default.
• W2099210514 cites W2056242268 @default.
• W2099210514 cites W2056722718 @default.
• W2099210514 cites W2058510817 @default.
• W2099210514 cites W2059428635 @default.
• W2099210514 cites W2065707109 @default.
• W2099210514 cites W2066576431 @default.
• W2099210514 cites W2066911071 @default.
• W2099210514 cites W2067763535 @default.
• W2099210514 cites W2068264240 @default.
• W2099210514 cites W2068666675 @default.
• W2099210514 cites W2071401061 @default.
• W2099210514 cites W2071455021 @default.
• W2099210514 cites W2073203446 @default.
• W2099210514 cites W2076752122 @default.
• W2099210514 cites W2079463010 @default.
• W2099210514 cites W2081003442 @default.
• W2099210514 cites W2081210383 @default.
• W2099210514 cites W2086741450 @default.
• W2099210514 cites W2087826935 @default.
• W2099210514 cites W2089315718 @default.
• W2099210514 cites W2092673001 @default.
• W2099210514 cites W2099527698 @default.
• W2099210514 cites W2103320610 @default.
• W2099210514 cites W2114207424 @default.
• W2099210514 cites W2121278452 @default.
• W2099210514 cites W2124001309 @default.

• next