Inhaltszusammenfassung

Trapped atomic ions in microfabricated segmented ion traps hold the promise of realizing scalable quantum processing nodes. While significant milestones towards noisy intermediate-scale quantum computing (NISQ) have already been demonstrated in the past decade, the realization of platforms allowing for demonstration of e.g. quantum supremacy remains a formidable challenge. Scalability to large number of qubits can be achieved using a combination of trapped-ion qubits that are shuttled inside ...Trapped atomic ions in microfabricated segmented ion traps hold the promise of realizing scalable quantum processing nodes. While significant milestones towards noisy intermediate-scale quantum computing (NISQ) have already been demonstrated in the past decade, the realization of platforms allowing for demonstration of e.g. quantum supremacy remains a formidable challenge. Scalability to large number of qubits can be achieved using a combination of trapped-ion qubits that are shuttled inside a segmented ion trap and manipulated in laser interaction zones. The focus of this thesis is the development of technological key components required for this approach, perform system integration with an existing hardware environment, and to conduct a comprehensive characterization of the system performance. In particular, we discuss the development of a modular based scalable multichannel arbitrary waveform generator (mAWG), which simultaneously updates 80 trap electrodes with programmable voltage waveforms and shapes the duration of 24 laser pulses for entangling gate operations. It has an update rate of 2.7 MSPS for each channel and voltage range of +/-40 V with the precision of 1.2 mV. Additionally, the delay between consecutive samples can be controlled in step of 20 ns - important for resolving trap oscillation period during shuttling of ions. Furthermore, using the mAWG, we present a complete trap-characterization of all motional modes, axial (x) along the trap axis and transverse (y and z) perpendicular to it, for a Ca+ ion, obtaining low heating rates, {n_bar}_{x,y,z}={9, 26.6(7), 9.2(3)}, and a long motional coherence times of τ{x,y,z}={57(9), 11.6(5), 24(1)} ms. We also realize various types of elementary qubit register configuration i.e. linear transport, separation and merging of ion crystals, and ion swapping and measure no excitation on the transverse mode induced by these axial shuttling operations, such that two qubit gates with fidelity exceeding 99.5% have been realized. This opens up a path toward NISQ realization. We also show that using this hardware, all type of shuttling operations and even can be executed in parallel at durations of less than 60 us, thus being well suited for small-scale quantum algorithms. Lastly, we discuss the prospect of scalability in this NISQ platform.» weiterlesen» einklappen

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Klassifikation

DDC Sachgruppe:
Physik