Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 21 for “"Dynamical Decoupling"”.
-
Decoherence and Dynamical Decoupling in Solid-State Spin Qubits
… any ideal pulse sequence applied to the qubit. Dynamical decoupling sequences, which aim to prolong qubit coherence, are analyzed. In particular, concatenated dynamical decoupling sequences are shown to prolong not only the coherence time over the entire sequence but also the length of time …
-
Nanoscale nuclear spin imaging: Dynamical decoupling and diffraction in a magnetic resonance force microscope
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2023-05-01
-
Study and Application of the Space Curve Quantum Control Formalism
… Here we introduce an SCQC Formalism based on dynamical decoupling and reverse engineering. Space Curve Quantum Control Formalism discovers the tight connections between quantum, geometric, and classical systems. We are able to use such connections to build noise-canceling, precise control, and …
-
Quantum control of spin systems in diamond
… quantum sensing tasks. We develop a continuous dynamical decoupling (CoDD) method that allows us to tune the degree of protection from a dephasing environment. Exploiting this flexibility, we show that the CoDD can be used to measure magnetic fields with sensitivity comparable to existing …
-
State-selective imaging of single rubidium atoms in a solid neon matrix
… on the order of tens of microseconds. By using dynamical decoupling techniques, we obtain ultralong spin-coherence times T2 on the order of 0.1 s. We also show that the dynamical decoupling sequence turns the atoms into an effective AC magnetometer. We use the atoms to detect the nuclear …
-
Digital noise reconstruction with a quantum sensor
… the noise spectrum in frequency domain using dynamical decoupling sequences. In this thesis, we propose a novel digital noise reconstruction method to reconstruct the environmental noise both in frequency and time domains, which avoids the delta function approximation for frequency filtering. …
-
Non-Gaussian Noise in Superconducting Circuits
… a qubit system. I achieve this using multi-qubit dynamical decoupling sequences that characterize noise during two-qubit gates when the system is coupled strongly to flux fluctuations. This noise is qualitatively different from the well-studied noise that leads to single qubit dephasing; it …
-
Quantum Information Processing with Color Center Qubits: Theory of Initialization and Robust Control
… color centers in silicon carbide. I also provide dynamical decoupling-based high-fidelity control of nuclear spins around the color center. I also present a control technique that combines holonomic control and dynamically corrected control to tolerate simultaneous errors from various sources. The …
-
Coherence characterization with a superconducting flux qubit through NMR approaches
… are implemented. In particular, one type of dynamical decoupling techniques that uses refocusing pulses to recover coherence is successfully realized for the first time. This technique is further utilized as a noise spectrum analyzer in the megahertz range, by which a 1/f-type dependence is …
-
Quantum sensing and simulation with solid-state defects
… we exploit the modulated driving to simulate dynamical symmetries and characterize their selection rules using projective measurements of the coherence evolution of the system. The same control technique is shown to further design parallel quantum gates for atom array quantum platforms. …
-
Precise control of quantum information
… concatenation of quantum error correction with dynamical decoupling. The gates were also used to demonstrate the quantum Fourier transform, the disentanglement eraser, and an entanglement swap. Finally, we describe a nuclear magnetic resonance (NMR) implementation of a quantum lattice gas (QLG) …
-
Coherent control of electron spins in diamond for quantum information science and quantum sensing
… method generalizes sampling techniques based on dynamical decoupling sequences and enables measuring the temporal profile of time-varying magnetic fields in the presence of dephasing noise. We then introduce and experimentally demonstrate coherent control techniques to identify, integrate, and …
-
The tin-vacancy centre in diamond: a coherent spin-photon interface for quantum network nodes
… with highly spin-selective optical transitions. Dynamical decoupling protocols are used to protect the spin coherence for up to 5.7(11) ms. We identify the properties of the spin bath, allowing us to understand material engineering challenges for next-generation devices. The crystal strain …
-
Quantum technologies with superconducting artificial atoms
… by means of optimal symmetry breaking and dynamical decoupling. Stimulated Raman Adiabatic Passage (STIRAP), an adiabatic population transfer technique in three-level system, is introduced and its transfer efficiency is shown to be around 70% in the Cooper Pair Box. Optimization strategies …
-
Developing the spin qubit of the tin-vacancy center in diamond for quantum networks
… inhomogenous coherence time T2* = 1.3(3) μs and dynamical decoupling protocols prolonging the coherence time to T2 = 300(80) μs at 1.7 K. These results establish that the SnV center possesses the desired combination of spin and photonic properties necessary to be the building block for the …
-
Dynamically Corrected Quantum Control: A Geometrical Framework
… Hahn spin echo or CPMG, have been developed to dynamically correcting the noise effects. However, implementing these ideal pulses with high fidelity is a challenging task in real experiments. In this thesis, we provide a new and simple method to explore the entire solution space of driving pulse …
-
Tuning the coherent electron-nuclear interaction in a semiconductor quantum dot
… via electron spin resonance spectroscopy and dynamical decoupling pulse sequences. Further, by selecting the mean-field nuclear polarization, the strength of the electro-nuclear interaction can be controllably varied. This in turn enables the activation rate of collective nuclear excitations – …
-
Interfacing spin-based quantum sensors with complex systems
… nanoscale sensing volume. In this experiment a dynamical decoupling sequence is used to sense the stochastic and stationary magnetic field at the site of the NV created by the target nuclear spins. The spectral resolution of this technique is sufficient to distinguish between two different …
-
Diamond nanophotonic devices for quantum information processing and sensing
… photon count rate of 2.7 ± 0.09 Mcps. By using dynamical decoupling sequences, we measured a spin coherence time of 1.7 ± 0.1 ms, which is comparable to the highest reported spin coherence times of NVs under ambient conditions and also indicates that the bullseye fabrication process does not …
-
High Fidelity Universal Gates Performed on a Continuously-Decoupled Coherence Enhanced Transmon Qubit
<p>Decoherence is the primary limiting factor for the utility of modern qubits and qubit networks; most chiefly, pure dephasing which limits the operational time any gate-sequence can produce a high-fidelity result. In this dissertation, I present the results of my experiment, performing fast, high …
Page 1 of 2