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Yi Yin

Bio: Yi Yin is an academic researcher from Zhejiang University. The author has contributed to research in topics: Qubit & Phase qubit. The author has an hindex of 32, co-authored 86 publications receiving 4598 citations. Previous affiliations of Yi Yin include University of California, Berkeley & Nanjing University.


Papers
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Journal ArticleDOI
TL;DR: This work demonstrates a planar, tunable superconducting qubit with energy relaxation times up to 44 μs and finds a fine structure in the qubit energy lifetime as a function of frequency, indicating the presence of a sparse population of incoherent, weakly coupled two-level defects.
Abstract: We demonstrate a planar, tunable superconducting qubit with energy relaxation times up to 44 μs. This is achieved by using a geometry designed to both minimize radiative loss and reduce coupling to materials-related defects. At these levels of coherence, we find a fine structure in the qubit energy lifetime as a function of frequency, indicating the presence of a sparse population of incoherent, weakly coupled two-level defects. We elucidate this defect physics by experimentally varying the geometry and by a model analysis. Our "Xmon" qubit combines facile fabrication, straightforward connectivity, fast control, and long coherence, opening a viable route to constructing a chip-based quantum computer.

693 citations

Journal ArticleDOI
TL;DR: In this paper, the authors describe the fabrication and measurement of microwave coplanar waveguide resonators with internal quality factors above 107 at high microwave powers and over 106 at low powers, with the best low power results approaching 2×106.
Abstract: We describe the fabrication and measurement of microwave coplanar waveguide resonators with internal quality factors above 107 at high microwave powers and over 106 at low powers, with the best low power results approaching 2×106, corresponding to ∼1 photon in the resonator. These quality factors are achieved by controllably producing very smooth and clean interfaces between the resonators’ aluminum metallization and the underlying single crystal sapphire substrate. Additionally, we describe a method for analyzing the resonator microwave response, with which we can directly determine the internal quality factor and frequency of a resonator embedded in an imperfect measurement circuit.

371 citations

Journal ArticleDOI
TL;DR: In this article, the authors describe the fabrication and measurement of microwave coplanar waveguide resonators with internal quality factors above 10 million at high microwave powers and over 1 million at low powers, with the best low power results approaching 2 million.
Abstract: We describe the fabrication and measurement of microwave coplanar waveguide resonators with internal quality factors above 10 million at high microwave powers and over 1 million at low powers, with the best low power results approaching 2 million, corresponding to ~1 photon in the resonator. These quality factors are achieved by controllably producing very smooth and clean interfaces between the resonators' aluminum metallization and the underlying single crystal sapphire substrate. Additionally, we describe a method for analyzing the resonator microwave response, with which we can directly determine the internal quality factor and frequency of a resonator embedded in an imperfect measurement circuit.

349 citations

Journal ArticleDOI
30 Sep 2010-Nature
TL;DR: The operation of three coupled superconducting phase qubits are demonstrated and used to create and measure |GHZ〉 and |W〉 states and are shown to satisfy entanglement witnesses, confirming that they are indeed examples of three-qubitEntanglement and are not separable into mixtures of two-qubits.
Abstract: Quantum entanglement, in which the states of two or more particles are inextricably linked, is a key requirement for quantum computation. In superconducting devices, two-qubit entangled states have been used to implement simple quantum algorithms. The availability of three-qubit states, which can be entangled in two fundamentally different ways (the GHZ and W states), would be a significant advance because they should make it possible to perform error correction and infer scalability to the higher numbers of qubits needed for a practical quantum-information-processing device. Two groups now report the generation of three-qubit entanglement. John Martinis and colleagues create and measure both GHZ and W-type states. Leonardo DiCarlo and colleagues generate the GHZ state and demonstrate the first step of basic quantum error correction by encoding a logical qubit into a manifold of GHZ-like states using a repetition code. Quantum entanglement is one of the key resources required for quantum computation. In superconducting devices, two-qubit entangled states have been used to implement simple quantum algorithms, but three-qubit states, which can be entangled in two fundamentally different ways, have not been demonstrated. Here, however, three superconducting phase qubits have been used to create and measure these two entangled three-qubit states. Entanglement is one of the key resources required for quantum computation1, so the experimental creation and measurement of entangled states is of crucial importance for various physical implementations of quantum computers2. In superconducting devices3, two-qubit entangled states have been demonstrated and used to show violations of Bell’s inequality4 and to implement simple quantum algorithms5. Unlike the two-qubit case, where all maximally entangled two-qubit states are equivalent up to local changes of basis, three qubits can be entangled in two fundamentally different ways6. These are typified by the states |GHZ〉 = (|000〉 + |111〉)/ and |W〉 = (|001〉 + |010〉 + |100〉)/ . Here we demonstrate the operation of three coupled superconducting phase qubits7 and use them to create and measure |GHZ〉 and |W〉 states. The states are fully characterized using quantum state tomography8 and are shown to satisfy entanglement witnesses9, confirming that they are indeed examples of three-qubit entanglement and are not separable into mixtures of two-qubit entanglement.

349 citations

Journal ArticleDOI
TL;DR: Shor's quantum algorithm factorizes integers as discussed by the authors, and implementing this is a benchmark test in the early development of quantum processors, and it has been used to demonstrate this important test in a solid-state system.
Abstract: Shor’s quantum algorithm factorizes integers, and implementing this is a benchmark test in the early development of quantum processors. Researchers now demonstrate this important test in a solid-state system: a circuit made up of four superconducting qubits factorizes the number 15.

308 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, an updated version of supplementary information to accompany "Quantum supremacy using a programmable superconducting processor", an article published in the October 24, 2019 issue of Nature, is presented.
Abstract: This is an updated version of supplementary information to accompany "Quantum supremacy using a programmable superconducting processor", an article published in the October 24, 2019 issue of Nature. The main article is freely available at this https URL. Summary of changes since arXiv:1910.11333v1 (submitted 23 Oct 2019): added URL for qFlex source code; added Erratum section; added Figure S41 comparing statistical and total uncertainty for log and linear XEB; new References [1,65]; miscellaneous updates for clarity and style consistency; miscellaneous typographical and formatting corrections.

4,873 citations

Journal ArticleDOI
TL;DR: The concept of the stabilizer, using two qubits, is introduced, and the single-qubit Hadamard, S and T operators are described, completing the set of required gates for a universal quantum computer.
Abstract: This article provides an introduction to surface code quantum computing. We first estimate the size and speed of a surface code quantum computer. We then introduce the concept of the stabilizer, using two qubits, and extend this concept to stabilizers acting on a two-dimensional array of physical qubits, on which we implement the surface code. We next describe how logical qubits are formed in the surface code array and give numerical estimates of their fault tolerance. We outline how logical qubits are physically moved on the array, how qubit braid transformations are constructed, and how a braid between two logical qubits is equivalent to a controlled-not. We then describe the single-qubit Hadamard, Ŝ and T operators, completing the set of required gates for a universal quantum computer. We conclude by briefly discussing physical implementations of the surface code. We include a number of Appendices in which we provide supplementary information to the main text. © 2012 American Physical Society.

2,205 citations

Journal ArticleDOI
08 Mar 2013-Science
TL;DR: For the first time, physicists will have to master quantum error correction to design and operate complex active systems that are dissipative in nature, yet remain coherent indefinitely.
Abstract: The performance of superconducting qubits has improved by several orders of magnitude in the past decade. These circuits benefit from the robustness of superconductivity and the Josephson effect, and at present they have not encountered any hard physical limits. However, building an error-corrected information processor with many such qubits will require solving specific architecture problems that constitute a new field of research. For the first time, physicists will have to master quantum error correction to design and operate complex active systems that are dissipative in nature, yet remain coherent indefinitely. We offer a view on some directions for the field and speculate on its future.

2,013 citations