arXiv subjects

Erik Streed

Publications and source records attributed to Erik Streed.

3 recordsLinked to original sources

arXiv2021

Ultrafast coherent excitation of an Ytterbium ion with single laser pulses

Experimental realizations of two qubit entangling gates with trapped ions typically rely on addressing spectroscopically resolved motional sidebands, limiting gate speed to the secular frequency. Fast entangling gates using ultrafast pulsed lasers overcome this speed limit. This approach is based on state-dependent photon recoil kicks from a sequence of counter-propagating, resonant, ultrafast pulse pairs, which can allow sub-microsecond gate speeds. Here we demonstrate a key component of the ultrafast gate protocol, the coherent excitation of a 171Yb+ ion across the 2S1/2-2P1/2 transition with a single near-resonant short optical pulse at 369.53 nm. We achieve a maximum population transfer of 94.3(6)% using a picosecond pulsed laser that can be tuned across the 2S1/2-2P1/2 transition, and 42.53(13)% with 190(7) GHz detuning.

quant-ph↗

arXiv2020

Studies of thorium and ytterbium ion trap loading from laser ablation for gravity monitoring with nuclear clocks

Compact and robust ion traps for thorium are enabling technology for the next generation of atomic clocks based on a low-energy isomeric transition in the thorium-229 nucleus. We aim at a laser ablation loading of single triply ionized thorium in a radio-frequency electromagnetic linear Paul trap. Detection of ions is based on a modified mass spectrometer and a channeltron with single-ion sensitivity. In this study, we successfully created and detected 232Th+ and 232Th2+ ions from plasma plumes, studied their yield evolution, and compared the loading to a quadrupole ion trap with Yb. We explore the feasibility of laser ablation loading for future low-cost 229Th3+ trapping. The thorium ablation yield shows a strong depletion, suggesting that we have ablated oxide layers from the surface and the ions were a result of the plasma plume evolution and collisions. Our results are in good agreement with similar experiments for other elements and their oxides.

physics.atom-ph↗

arXiv2020

Multi-channel Opto-mechanical Switch and Locking System for Wavemeters

Here we present a cost effective multi-channel opto-mechanical switch and software PID system for locking multiple lasers to a single channel commercial wavemeter. The switch is based on a rotating cylinder that selectively transmits one laser beam at a time to the wavemeter, the wavelength is read by the computer and an error signal is output to the lasers to correct wavelength drifts every millisecond. We use this system to stabilise 740 nm (subsequently frequency doubled to 370 nm), 399 nm and 935 nm lasers for trapping and cooling different isotopes of Yb+ ion. We characterize the frequency stability of the three lasers by using a second, more precise, commercial wavemeter. We also characterise the absolute frequency stability of the 740 nm laser using the fluorescence drift rate of a trapped 174Yb+ ion. For the 740 nm laser we demonstrate an Allan deviation, df/f, of 3 x 10^-10 (at 20 s integration time), equivalent to sub-200 KHz stability.

physics.optics↗