Single Flux Quantum-Based Digital Control of Superconducting Qubits in a Multi-Chip Module

• URL: http://arxiv.org/abs/2301.05696v1
• Date: Fri, 13 Jan 2023 18:37:08 GMT
• Title: Single Flux Quantum-Based Digital Control of Superconducting Qubits in a Multi-Chip Module
• Authors: Chuan-Hong Liu, Andrew Ballard, David Olaya, Daniel R. Schmidt, John Biesecker, Tammy Lucas, Joel Ullom, Shravan Patel, Owen Rafferty, Alexander Opremcak, Kenneth Dodge, Vito Iaia, Tianna McBroom, Jonathan L. Dubois, Pete F. Hopkins, Samuel P. Benz, Britton L. T. Plourde, Robert McDermott
• Abstract summary: We introduce a multi-chip module architecture to suppress phonon-mediated QP poisoning. We demonstrate an error per Clifford gate of 1.2(1)%, an order-of-magnitude reduction over the gate error achieved in the initial realization of SFQ-based qubit control.
• Score: 39.5906786952554
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The single flux quantum (SFQ) digital superconducting logic family has been proposed for the scalable control of next-generation superconducting qubit arrays. In the initial implementation, SFQ-based gate fidelity was limited by quasiparticle (QP) poisoning induced by the dissipative on-chip SFQ driver circuit. In this work, we introduce a multi-chip module architecture to suppress phonon-mediated QP poisoning. Here, the SFQ elements and qubits are fabricated on separate chips that are joined with In bump bonds. We use interleaved randomized benchmarking to characterize the fidelity of SFQ-based gates, and we demonstrate an error per Clifford gate of 1.2(1)%, an order-of-magnitude reduction over the gate error achieved in the initial realization of SFQ-based qubit control. We use purity benchmarking to quantify the contribution of incoherent error at 0.96(2)%; we attribute this error to photon-mediated QP poisoning mediated by the resonant mm-wave antenna modes of the qubit and SFQ-qubit coupler. We anticipate that a straightforward redesign of the SFQ driver circuit to limit the bandwidth of the SFQ pulses will eliminate this source of infidelity, allowing SFQ-based gates with fidelity approaching theoretical limits, namely 99.9% for resonant sequences and 99.99% for more complex pulse sequences involving variable pulse-to-pulse separation.

Related papers

• Speeding up qubit control with bipolar single-flux-quantum pulse sequences [0.0]
  We introduce the bipolar SFQ pulse control based on ternary pulse sequences. We show that the appropriate sequence can be found for arbitrary system parameters from the practical range. The proposed bipolar SFQ control reduces a single qubit gate time by halve compared to nowadays unipolar SFQ technique.
  arXiv  Detail & Related papers  (2023-10-17T14:44:02Z)
• Compact Pulse Schedules for High-Fidelity Single-Flux Quantum Qubit Control [0.0]
  Single-flux quantum (SFQ) pulses can be used to control superconducting qubits. We propose pulse sequences that can be stored in 22 bits or fewer, with gate fidelities exceeding 99.99%. This modest memory requirement could help reduce the footprint of the SFQ coprocessors and power dissipation.
  arXiv  Detail & Related papers  (2023-09-08T21:33:00Z)
• Single-flux-quantum-based Qubit Control with Tunable Driving Strength [14.8865192054034]
  Single-flux-quantum (SFQ) circuits have great potential in building cryogenic quantum-classical interfaces for scaling up superconducting quantum processors. Current control schemes are difficult to tune the driving strength to qubits, which restricts the gate length and usually induces leakage to unwanted levels. In this study, we design the scheme and corresponding pulse generator circuit to continuously adjust the driving strength by coupling SFQ pulses with variable intervals.
  arXiv  Detail & Related papers  (2023-07-26T12:12:30Z)
• Quasiparticle Dynamics in Superconducting Quantum-Classical Hybrid Circuits [4.556590964168528]
  Single flux quantum (SFQ) circuitry is a promising candidate for a scalable and integratable cryogenic quantum control system. In this study, we investigate non-equilibrium quasiparticles (QPs) in a superconducting quantum-classical hybrid chip.
  arXiv  Detail & Related papers  (2023-07-26T11:54:44Z)
• Quantum Key Distribution Using a Quantum Emitter in Hexagonal Boron Nitride [48.97025221755422]
  We demonstrate a room temperature, discrete-variable quantum key distribution system using a bright single photon source in hexagonal-boron nitride. We have generated keys with one million bits length, and demonstrated a secret key of approximately 70,000 bits, at a quantum bit error rate of 6%. Our work demonstrates the first proof of concept finite-key BB84 QKD system realised with hBN defects.
  arXiv  Detail & Related papers  (2023-02-13T09:38:51Z)
• 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)
• Practical implications of SFQ-based two-qubit gates [3.4982242928569405]
  Scalability of today's superconducting quantum computers is limited due to the huge costs of generating/routing microwave control pulses per qubit from room temperature. One active research area in both industry and academia is to push the classical controllers to the dilution refrigerator in order to increase the scalability of quantum computers. Superconducting Single Flux Quantum (SFQ) is a classical logic technology with low power consumption and ultra-high speed.
  arXiv  Detail & Related papers  (2022-02-03T05:05:24Z)
• Coherent effects contribution to a fast gate fidelity in ion quantum computer [47.187609203210705]
  We develop a numerical model for full simulation of coherence effects using a linear ion microtrap array and a 2D microtrap array. We have also studied the dependency of the gate fidelity on the laser power fluctuations.
  arXiv  Detail & Related papers  (2021-12-12T12:53:00Z)
• Sampling Overhead Analysis of Quantum Error Mitigation: Uncoded vs. Coded Systems [69.33243249411113]
  We show that Pauli errors incur the lowest sampling overhead among a large class of realistic quantum channels. We conceive a scheme amalgamating QEM with quantum channel coding, and analyse its sampling overhead reduction compared to pure QEM.
  arXiv  Detail & Related papers  (2020-12-15T15:51:27Z)
• 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)

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.