Qubit measurement error from coupling with a detuned neighbor in circuit QED

@article{Khezri2015QubitME,
  title={Qubit measurement error from coupling with a detuned neighbor in circuit QED},
  author={Mostafa Khezri and Justin Dressel and Alexander N. Korotkov},
  journal={Physical Review A},
  year={2015},
  volume={92},
  pages={052306}
}
© 2015 American Physical Society. In modern circuit QED architectures, superconducting transmon qubits are measured via the state-dependent phase and amplitude shift of a microwave field leaking from a coupled resonator. Determining this shift requires integrating the field quadratures for a nonzero duration, which can permit unwanted concurrent evolution. Here we investigate such dynamical degradation of the measurement fidelity caused by a detuned neighboring qubit. We find that in realistic… Expand
Dispersive Measurement of Superconducting Qubits
Author(s): Khezri, Mostafa | Advisor(s): Korotkov, Alexander N. | Abstract: Quantum computers have the capability to improve the efficiency and speed of many computational tasks. Among differentExpand
Quantum-limited measurement of spin qubits via curvature couplings to a cavity
We investigate coupling an encoded spin qubit to a microwave resonator via qubit energy level curvature versus gate voltage. This approach enables quantum non-demolition readout with strength of tensExpand
Transmon platform for quantum computing challenged by chaotic fluctuations
From the perspective of many body physics, the transmon qubit architectures currently developed for quantum computing are systems of coupled nonlinear quantum resonators. A significant amount ofExpand
Coherent state transfer between superconducting qubits via stimulated Raman adiabatic passage
  • Danyu Li, Wen Zheng, +11 authors Yang Yu
  • Physics
  • 2021
Coherent quantum state transfer is a vital step in quantum information processing. Based on the stimulated Raman adiabatic passage (STIRAP), we realize robust quantum state transfer between twoExpand
JigSaw: Boosting Fidelity of NISQ Programs via Measurement Subsetting
Near-term quantum computers contain noisy devices, which makes it difficult to infer the correct answer even if a program is run for thousands of trials. On current machines, qubit measurements tendExpand
Quantum supremacy using a programmable superconducting processor
TLDR
Quantum supremacy is demonstrated using a programmable superconducting processor known as Sycamore, taking approximately 200 seconds to sample one instance of a quantum circuit a million times, which would take a state-of-the-art supercomputer around ten thousand years to compute. Expand
Maximal adaptive-decision speedups in quantum-state readout
TLDR
This work reformulates this readout problem in terms of the first-passage time of a particle undergoing stochastic motion to theoretically establish the maximum achievable adaptive-decision speedups for several physical two-state readout implementations and proposes a simple readout scheme for which the speedup can, in principle, be increased without bound as the fidelity is increased. Expand
Out-of-Time-Ordered-Correlator Quasiprobabilities Robustly Witness Scrambling.
TLDR
It is demonstrated empirically that the nonclassical negativity of the quasiprobability distribution (QPD) behind the OTOC is a more sensitive witness for scrambling than the OT OC itself, which is based on quantum-computing hardware such as superconducting qubits and trapped ions. Expand
Modulated longitudinal gates on encoded spin qubits via curvature couplings to a superconducting cavity
We propose entangling operations based on the energy curvature couplings of encoded spin qubits to a superconducting cavity, exploring the nonlinear qubit response to a gate voltage variation. For aExpand
What is measured when a qubit measurement is performed on a multiqubit chip
We study how single-qubit dispersive readout works alongside two qubit coupling. To make calculations analytically tractable, we use a simplified model which retains core characteristics of but isExpand

References

SHOWING 1-10 OF 134 REFERENCES
Dispersive regime of circuit QED : Photon-dependent qubit dephasing and relaxation rates
Superconducting electrical circuits can be used to study the physics of cavity quantum electrodynamics (QED) in new regimes, therefore realizing circuit QED. For quantum-information processing andExpand
Qubit-photon interactions in a cavity: Measurement-induced dephasing and number splitting
We theoretically study measurement-induced dephasing of a superconducting qubit in the circuit QED architecture and compare the results to those obtained experimentally by Schuster et al. [Phys. Rev.Expand
Deterministic entanglement of superconducting qubits by parity measurement and feedback
TLDR
Here, a time-resolved, continuous parity measurement of two superconducting qubits is performed using the cavity in a three-dimensional circuit quantum electrodynamics architecture and phase-sensitive parametric amplification to produce entanglement by parity measurement reaching 88 per cent fidelity to the closest Bell state. Expand
Quantum theory of a bandpass Purcell filter for qubit readout
© 2015 American Physical Society. ©2015 American Physical Society. The measurement fidelity of superconducting transmon and Xmon qubits is partially limited by the qubit energy relaxation through theExpand
Protocols for optimal readout of qubits using a continuous quantum nondemolition measurement
We study how the spontaneous relaxation of a qubit affects a continuous quantum nondemolition measurement of the initial state of the qubit. Given some noisy measurement record {psi}, we seek anExpand
Quantum trajectory approach to circuit QED: Quantum jumps and the Zeno effect
We present a theoretical study of a superconducting charge qubit dispersively coupled to a transmission line resonator. Starting from a master equation description of this coupled system and using aExpand
Cavity quantum electrodynamics for superconducting electrical circuits: An architecture for quantum computation
We propose a realizable architecture using one-dimensional transmission line resonators to reach the strong-coupling limit of cavity quantum electrodynamics in superconducting electrical circuits.Expand
Fast reset and suppressing spontaneous emission of a superconducting qubit
Spontaneous emission through a coupled cavity can be a significant decay channel for qubits in circuit quantum electrodynamics. We present a circuit design that effectively eliminates spontaneousExpand
Resonator-zero-qubit architecture for superconducting qubits
We analyze the performance of the resonator–zero-qubit (RezQu) architecture in which the qubits are complemented by memory resonators and coupled via a resonator bus. Separating the storedExpand
Implementing a strand of a scalable fault-tolerant quantum computing fabric.
TLDR
High-fidelity parity detection of two code qubits via measurement of a third syndrome qubit is demonstrated and a measurement tomography protocol is developed to fully characterize this parity readout. Expand
...
1
2
3
4
5
...