Universal pulses for superconducting qudit ladder gates

• URL: http://arxiv.org/abs/2412.18339v2
• Date: Sun, 19 Jan 2025 16:01:43 GMT
• Title: Universal pulses for superconducting qudit ladder gates
• Authors: Boxi Li, F. A. Cárdenas-López, Adrian Lupascu, Felix Motzoi,
• Abstract summary: We present a universal pulse construction for generating rapid, high-fidelity unitary rotations between adjacent qudit levels. We derive concise analytical pulse schemes that suppress multiple control errors and outperform existing methods.
• Score: 0.0
• License:
• Abstract: Qudits, generalizations of qubits to multi-level quantum systems, offer enhanced computational efficiency by encoding more information per lattice cell, avoiding costly swap operations and providing even exponential speedup in some cases. Utilizing the $d$-level manifold, however, requires high-speed gate operations because of the stronger decoherence at higher levels. While analytical control methods have proven effective for qubits in achieving fast gates with minimal control errors, their extension to qudits is nontrivial due to the increased complexity of the energy level structure arising from additional ancillary states. In this work, we present a universal pulse construction for generating rapid, high-fidelity unitary rotations between adjacent qudit levels, thereby providing a prescription for any gate in $SU(d)$. Control errors in these operations are effectively analyzed within a four-level subspace, including two leakage levels with approximately opposite detuning. By identifying the optimal degrees of freedom, we derive concise analytical pulse schemes that suppress multiple control errors and outperform existing methods. Remarkably, our approach achieves consistent coherent error scaling across all levels, approaching the quantum speed limit independently of parameter variations between levels. Validation on transmon circuits demonstrates significant improvements in gate fidelity for various qudit sizes aiming for $10^{-4}$ error. This method provides a scalable solution for improving qudit control and can be broadly applied to other quantum systems with ladder structures or operations involving multiple ancillary levels.

Related papers

• Full Qubit Control in the NV$^-$ Ground State for Low Field or High Frequency Sensing [0.0]
  We present a scheme for the implementation of fast arbitrary qubit gates in the ground state of the negatively charged nitrogen-vacancy defect in diamond. The protocol is especially useful in the low-field regime and for high-frequency sensing applications.
  arXiv  Detail & Related papers  (2024-07-24T17:58:16Z)
• Fast Flux-Activated Leakage Reduction for Superconducting Quantum Circuits [84.60542868688235]
  leakage out of the computational subspace arising from the multi-level structure of qubit implementations. We present a resource-efficient universal leakage reduction unit for superconducting qubits using parametric flux modulation. We demonstrate that using the leakage reduction unit in repeated weight-two stabilizer measurements reduces the total number of detected errors in a scalable fashion.
  arXiv  Detail & Related papers  (2023-09-13T16:21:32Z)
• Optimizing quantum gates towards the scale of logical qubits [78.55133994211627]
  A foundational assumption of quantum gates theory is that quantum gates can be scaled to large processors without exceeding the error-threshold for fault tolerance. Here we report on a strategy that can overcome such problems. We demonstrate it by choreographing the frequency trajectories of 68 frequency-tunablebits to execute single qubit while superconducting errors.
  arXiv  Detail & Related papers  (2023-08-04T13:39:46Z)
• Hybrid Gate-Pulse Model for Variational Quantum Algorithms [33.73469431747376]
  Current quantum programs are mostly compiled on the gate-level, where quantum circuits are composed of quantum gates. pulse-level optimization has gained more attention from researchers due to their advantages in terms of circuit duration. We present a hybrid gate-pulse model that can mitigate these problems.
  arXiv  Detail & Related papers  (2022-12-01T17:06:35Z)
• Multi-squeezed state generation and universal bosonic control via a driven quantum Rabi model [68.8204255655161]
  Universal control over a bosonic degree of freedom is key in the quest for quantum-based technologies. Here we consider a single ancillary two-level system, interacting with the bosonic mode of interest via a driven quantum Rabi model. We show that it is sufficient to induce the deterministic realization of a large class of Gaussian and non-Gaussian gates, which in turn provide universal bosonic control.
  arXiv  Detail & Related papers  (2022-09-16T14:18:53Z)
• Erasure qubits: Overcoming the $T_1$ limit in superconducting circuits [105.54048699217668]
  amplitude damping time, $T_phi$, has long stood as the major factor limiting quantum fidelity in superconducting circuits. We propose a scheme for overcoming the conventional $T_phi$ limit on fidelity by designing qubits in a way that amplitude damping errors can be detected and converted into erasure errors.
  arXiv  Detail & Related papers  (2022-08-10T17:39:21Z)
• Fast and Robust Geometric Two-Qubit Gates for Superconducting Qubits and beyond [0.0]
  We propose a scheme to realize robust geometric two-qubit gates in multi-level qubit systems. Our scheme is substantially simpler than STIRAP-based gates that have been proposed for atomic platforms. We show how our gate can be accelerated using a shortcuts-to-adiabaticity approach.
  arXiv  Detail & Related papers  (2022-08-08T16:22:24Z)
• Fast high-fidelity composite gates in superconducting qubits: Beating the Fourier leakage limit [0.0]
  We present a method for quantum control in superconducting qubits, which overcomes the Fourier limit for the gate duration imposed by leakage to upper states. We use our approach to produce complete and partial population transfer between the qubit states, as well as the three basic single-qubit quantum gates.
  arXiv  Detail & Related papers  (2022-05-09T10:10:05Z)
• Speed limits for two-qubit gates with weakly anharmonic qubits [0.6738135972929344]
  We use optimal control theory to determine the maximum achievable gate speed for two-qubit gates. We analyze the effect of the additional quantum states on the gate speed.
  arXiv  Detail & Related papers  (2021-09-03T12:07:59Z)
• Realization of arbitrary doubly-controlled quantum phase gates [62.997667081978825]
  We introduce a high-fidelity gate set inspired by a proposal for near-term quantum advantage in optimization problems. By orchestrating coherent, multi-level control over three transmon qutrits, we synthesize a family of deterministic, continuous-angle quantum phase gates acting in the natural three-qubit computational basis.
  arXiv  Detail & Related papers  (2021-08-03T17:49:09Z)
• Quantum control landscape for ultrafast generation of single-qubit phase shift quantum gates [68.8204255655161]
  We consider the problem of ultrafast controlled generation of single-qubit phase shift quantum gates. Globally optimal control is a control which realizes the gate with maximal possible fidelity. Trap is a control which is optimal only locally but not globally.
  arXiv  Detail & Related papers  (2021-04-26T16:38:43Z)

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.