Enhancing qubit readout through dissipative sub-Poissonian dynamics

Abstract

Single-shot qubit readout typically combines high readout contrast with long-lived readout signals, leading to large signal-to-noise ratios and high readout fidelities. In recent years, it has been demonstrated that both readout contrast and readout signal lifetime, and thus the signal-to-noise ratio, can be enhanced by forcing the qubit state to transition through intermediate states. In this work, we demonstrate that the sub-Poissonian relaxation statistics introduced by intermediate states can reduce the single-shot readout error rate by orders of magnitude even when there is no increase in signal-to-noise ratio. These results hold for moderate values of the signal-to-noise ratio ($\mathcal{S}\lesssim 100$) and a small number of intermediate states ($N\lesssim 10$). The ideas presented here could have important implications for readout schemes relying on the detection of transient charge states, such as spin-to-charge conversion schemes for semiconductor spin qubits and parity-to-charge conversion schemes for topologically protected Majorana qubits.

10 pages, 6 figures. Two appendices have been added. This version is close to the final published version

References in corpus (34)

• Single-shot read-out of an individual electron spin in a quantum dot
• Single-shot readout of an electron spin in silicon
• High-fidelity projective readout of a solid-state spin quantum register
• High-fidelity preparation, gates, memory and readout of a trapped-ion quantum bit
• Scalable Designs for Quasiparticle-Poisoning-Protected Topological Quantum Computation with Majorana Zero Modes
• High-fidelity readout and control of a nuclear spin qubit in silicon
• Milestones toward Majorana-based quantum computing
• Fast Scalable State Measurement with Superconducting Qubits
• Realizing Rapid, High-Fidelity, Single-Shot Dispersive Readout of Superconducting Qubits
• High-fidelity readout of trapped-ion qubits
• Double quantum dot with integrated charge sensor based on Ge/Si heterostructure nanowires
• Measurement-Only Topological Quantum Computation
• Rapid Single-Shot Measurement of a Singlet-Triplet Qubit
• Single-shot qubit readout in circuit Quantum Electrodynamics
• Single-shot qubit readout in circuit Quantum Electrodynamics
• Majorana box qubits
• Efficient readout of a single spin state in diamond via spin-to-charge conversion
• Universal enhancement of the optical readout fidelity of single electron spins
• Protocols for optimal readout of qubits using a continuous quantum nondemolition measurement
• Cavity-based single atom preparation and high-fidelity hyperfine state readout
• High Speed, High Fidelity Detection of an Atomic Hyperfine Qubit
• Bends In Nanotubes Allow Electric Spin Control and Coupling
• Single-shot readout of multiple nuclear spin qubits in diamond under ambient conditions
• Numerical Methods for Stochastic Differential Equations
• Long-distance spin-spin coupling via floating gates
• Robust Single-Shot Spin Measurement with 99.5% Fidelity in a Quantum Dot Array
• Enhanced charge detection of spin qubit readout via an intermediate state
• Correlations and entanglement of microwave photons emitted in a cascade decay
• Shot noise suppression at 1D hopping
• Optimal post-processing for a generic single-shot qubit readout
• Maximal adaptive-decision speedups in quantum-state readout
• High Fidelity Qubit Readout with the Superconducting Low-Inductance Undulatory Galvanometer Microwave Amplifier
• High fidelity single-shot readout of a transmon qubit using a SLUG μwave amplifier
• Optimal signal processing for continuous qubit readout

Cited by in corpus (9)

• Spin Readout Techniques of the Nitrogen-Vacancy Center in Diamond
• Transmon qubit readout fidelity at the threshold for quantum error correction without a quantum-limited amplifier
• High-fidelity measurement of qubits encoded in multilevel superconducting circuits
• Demonstration of quantum volume 64 on a superconducting quantum computing system
• Optimal dispersive readout of a spin qubit with a microwave resonator
• Introduction to Quantum Error Correction and Fault Tolerance
• Robust readout of bosonic qubits in the dispersive coupling regime
• Optimal control in large open quantum systems: the case of transmon readout and reset
• Theory of the Simultaneous Transient Dispersive Readout of Multiple Spin Qubits