Verifying the analogy between transversely coupled spin-1/2 systems and inductively-coupled fluxoniums

• URL: http://arxiv.org/abs/2407.15450v1
• Date: Mon, 22 Jul 2024 08:07:35 GMT
• Title: Verifying the analogy between transversely coupled spin-1/2 systems and inductively-coupled fluxoniums
• Authors: Wei-Ju Lin, Hyunheung Cho, Yinqi Chen, Maxim G. Vavilov, Chen Wang, Vladimir E. Manucharyan,
• Abstract summary: We report a detailed characterization of two inductively coupled superconducting fluxonium qubits. Our circuit behaves very closely to the case of two transversely coupled spin-1/2 systems.
• Score: 2.5586221134859426
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We report a detailed characterization of two inductively coupled superconducting fluxonium qubits for implementing high-fidelity cross-resonance gates. Our circuit stands out because it behaves very closely to the case of two transversely coupled spin-1/2 systems. In particular, the generally unwanted static ZZ-term due to the non-computational transitions is nearly absent despite a strong qubit-qubit hybridization. Spectroscopy of the non-computational transitions reveals a spurious LC-mode arising from the combination of the coupling inductance and the capacitive links between the terminals of the two qubit circuits. Such a mode has a minor effect on our specific device, but it must be carefully considered for optimizing future designs.

Related papers

• Complementing the transmon by integrating a geometric shunt inductor [0.0]
  We show that the ZZ interaction between the two qubits is completely suppressed when they are flux-biased to have opposite-sign anharmonicities. The simplicity of this two-qubit-species circuit makes it promising for building large lattices of superconducting qubits with low coherent error and a rich gate set.
  arXiv  Detail & Related papers  (2024-10-14T12:06:57Z)
• Josephson bifurcation readout: beyond the monochromatic approximation [49.1574468325115]
  We analyze properties of bifurcation quantum detectors based on weakly nonlinear superconducting resonance circuits. This circuit can serve as an efficient detector of the quantum state of superconducting qubits.
  arXiv  Detail & Related papers  (2024-05-25T22:22:37Z)
• Designing high-fidelity two-qubit gates between fluxonium qubits [0.19528996680336308]
  We propose a two-qubit gate between fluxonium qubits for minimal error, speed, and control simplicity. Our architecture consists of two fluxoniums coupled via a linear resonator. We predict an open-system average CZ gate infidelity of $1.86 times 10-4$ in 70ns.
  arXiv  Detail & Related papers  (2024-03-12T01:56:21Z)
• High fidelity two-qubit gates on fluxoniums using a tunable coupler [47.187609203210705]
  Superconducting fluxonium qubits provide a promising alternative to transmons on the path toward large-scale quantum computing. A major challenge for multi-qubit fluxonium devices is the experimental demonstration of a scalable crosstalk-free multi-qubit architecture. Here, we present a two-qubit fluxonium-based quantum processor with a tunable coupler element.
  arXiv  Detail & Related papers  (2022-03-30T13:44:52Z)
• Double-Transmon Coupler: Fast Two-Qubit Gate with No Residual Coupling for Highly Detuned Superconducting Qubits [0.0]
  tunable couplers have become a key component for realizing high-fidelity two-qubit gates in superconducting quantum computers. We propose a design for this kind of tunable coupler, which is composed of two transmon qubits coupled through a common loop with an additional Josephson junction. Controlling the magnetic flux in the loop, we can achieve not only fast high-fidelity two-qubit gates, but also no residual coupling during idle time, where computational qubits are highly detuned fixed-frequency transmons.
  arXiv  Detail & Related papers  (2022-03-22T04:11:30Z)
• Tunable coupling scheme for implementing two-qubit gates on fluxonium qubits [0.0]
  The superconducting fluxonium circuit is an RF-SQUID-type flux qubit that uses a large inductance built from an array of Josephson junctions or a high kinetic inductance material. In contrast to the transmon qubit, the anharmonicity of fluxonium can be large and positive, allowing for better separation between the low energy qubit manifold of the circuit and higher-lying excited states. We propose a tunable coupling scheme for implementing two-qubit gates on fixed-frequency fluxonium qubits, biased at half flux quantum.
  arXiv  Detail & Related papers  (2021-07-24T07:21:01Z)
• Superconducting coupler with exponentially large on-off ratio [68.8204255655161]
  Tunable two-qubit couplers offer an avenue to mitigate errors in multiqubit superconducting quantum processors. Most couplers operate in a narrow frequency band and target specific couplings, such as the spurious $ZZ$ interaction. We introduce a superconducting coupler that alleviates these limitations by suppressing all two-qubit interactions with an exponentially large on-off ratio.
  arXiv  Detail & Related papers  (2021-07-21T03:03:13Z)
• Waveguide quantum optomechanics: parity-time phase transitions in ultrastrong coupling regime [125.99533416395765]
  We show that the simplest set-up of two qubits, harmonically trapped over an optical waveguide, enables the ultrastrong coupling regime of the quantum optomechanical interaction. The combination of the inherent open nature of the system and the strong optomechanical coupling leads to emerging parity-time (PT) symmetry. The $mathcalPT$ phase transition drives long-living subradiant states, observable in the state-of-the-art waveguide QED setups.
  arXiv  Detail & Related papers  (2020-07-04T11:02:20Z)
• Universal non-adiabatic control of small-gap superconducting qubits [47.187609203210705]
  We introduce a superconducting composite qubit formed from two capacitively coupled transmon qubits. We control this low-frequency CQB using solely baseband pulses, non-adiabatic transitions, and coherent Landau-Zener interference. This work demonstrates that universal non-adiabatic control of low-frequency qubits is feasible using solely baseband pulses.
  arXiv  Detail & Related papers  (2020-03-29T22:48:34Z)
• Switching dynamics of single and coupled VO2-based oscillators as elements of neural networks [55.41644538483948]
  We report on the switching dynamics of both single and coupled VO2-based oscillators, with resistive and capacitive coupling, and explore the capability of their application in neural networks. For the resistive coupling, it is shown that synchronization takes place at a certain value of the coupling resistance, though it is unstable and a synchronization failure occurs periodically. For the capacitive coupling, two synchronization modes, with weak and strong coupling, are found. The transition between these modes is accompanied by chaotic oscillations.
  arXiv  Detail & Related papers  (2020-01-07T02:16:04Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.