papers

Publications (35)

quant-ph2021

Optimized fermionic SWAP networks with equivalent circuit averaging for QAOA

Akel Hashim, Rich Rines, Victory Omole +6

The fermionic SWAP network is a qubit routing sequence that can be used to efficiently execute the Quantum Approximate Optimization Algorithm (QAOA). Even with a minimally-connecte…

quant-ph2024

Average circuit eigenvalue sampling on NISQ devices

Emilio Pelaez, Victory Omole, Pranav Gokhale +4

Average circuit eigenvalue sampling (ACES) was introduced by Flammia in arXiv:2108.05803 as a protocol to characterize the Pauli error channels of individual gates across the devic…

quant-ph2021

Leveraging Randomized Compiling for the QITE Algorithm

Jean-Loup Ville, Alexis Morvan, Akel Hashim +13

The success of the current generation of Noisy Intermediate-Scale Quantum (NISQ) hardware shows that quantum hardware may be able to tackle complex problems even without error corr…

quant-ph2023

Benchmarking quantum logic operations relative to thresholds for fault tolerance

Akel Hashim, Stefan Seritan, Timothy Proctor +6

Contemporary methods for benchmarking noisy quantum processors typically measure average error rates or process infidelities. However, thresholds for fault-tolerant quantum error c…

quant-ph2024

Hardware-Efficient Randomized Compiling

Neelay Fruitwala, Akel Hashim, Abhi D. Rajagopala +7

Randomized compiling (RC) is an efficient method for tailoring arbitrary Markovian errors into stochastic Pauli channels. However, the standard procedure for implementing the proto…

quant-ph2025

Efficient Generation of Multi-partite Entanglement between Non-local Superconducting Qubits using Classical Feedback

Akel Hashim, Ming Yuan, Pranav Gokhale +8

Quantum entanglement is one of the primary features which distinguishes quantum computers from classical computers. In gate-based quantum computing, the creation of entangled state…

quant-ph2022

Random-access quantum memory using chirped pulse phase encoding

James O'Sullivan, Oscar W. Kennedy, Kamanasish Debnath +9

As in conventional computing, key attributes of quantum memories are high storage density and, crucially, random access, or the ability to read from or write to an arbitrarily chos…

quant-ph2026

Time-series based quantum state discrimination

Samuel Jung, Neel Vora, Akel Hashim +2

Accurate quantum state readout is crucial for error correction and algorithms, but measurement errors are detrimental. Readout fidelity is typically limited by a poor signal-to-noi…

quant-ph2025

A Practical Introduction to Benchmarking and Characterization of Quantum Computers

Akel Hashim, Long B. Nguyen, Noah Goss +16

Rapid progress in quantum technology has transformed quantum computing and quantum information science from theoretical possibilities into tangible engineering challenges. Breakthr…

quant-ph2025

Quasi-Probabilistic Readout Correction of Mid-Circuit Measurements for Adaptive Feedback via Measurement Randomized Compiling

Akel Hashim, Arnaud Carignan-Dugas, Larry Chen +6

Quantum measurements are a fundamental component of quantum computing. However, on modern-day quantum computers, measurements can be more error prone than quantum gates, and are su…

quant-ph2023

Empowering high-dimensional quantum computing by traversing the dual bosonic ladder

Long B. Nguyen, Noah Goss, Karthik Siva +6

High-dimensional quantum information processing has emerged as a promising avenue to transcend hardware limitations and advance the frontiers of quantum technologies. Harnessing th…

quant-ph2023

Superstaq: Deep Optimization of Quantum Programs

Colin Campbell, Frederic T. Chong, Denny Dahl +21

We describe Superstaq, a quantum software platform that optimizes the execution of quantum programs by tailoring to underlying hardware primitives. For benchmarks such as the Berns…

quant-ph2025

Enhancing quantum noise characterization via extra energy levels

Senrui Chen, Akel Hashim, Noah Goss +3

Noise is a major challenge for building practical quantum computing systems. Precise characterization of quantum noise is crucial for developing effective error mitigation and corr…

quant-ph2025

Easier randomizing gates provide more accurate fidelity estimation

Debankan Sannamoth, Kristine Boone, Arnaud Carignan-Dugas +4

Accurate benchmarking of quantum gates is crucial for understanding and enhancing the performance of quantum hardware. A standard method for this is interleaved benchmarking, a tec…

quant-ph2025

Quantum Benchmarking of High-Fidelity Noise-Biased Operations on a Detuned-Kerr-Cat Qubit

Bingcheng Qing, Ahmed Hajr, Ke Wang +19

Ubiquitous noises in quantum systems remain a key obstacle to building quantum computers, necessitating the use of quantum error correction codes. Recently, error-correcting codes…

quant-ph2024

ML-Powered FPGA-based Real-Time Quantum State Discrimination Enabling Mid-circuit Measurements

Neel R. Vora, Yilun Xu, Akel Hashim +11

Similar to reading the transistor state in classical computers, identifying the quantum bit (qubit) state is a fundamental operation to translate quantum information. However, iden…

quant-ph2024

Efficiently improving the performance of noisy quantum computers

Samuele Ferracin, Akel Hashim, Jean-Loup Ville +7

Using near-term quantum computers to achieve a quantum advantage requires efficient strategies to improve the performance of the noisy quantum devices presently available. We devel…

quant-ph2022

Programmable Heisenberg interactions between Floquet qubits

Long B. Nguyen, Yosep Kim, Akel Hashim +9

The fundamental trade-off between robustness and tunability is a central challenge in the pursuit of quantum simulation and fault-tolerant quantum computation. In particular, many…

quant-ph2026

A Qutrit Time Crystal Stabilized with Native Chiral Interactions

Noah Goss, Nishchay Suri, Brian Marinelli +11

Periodically driven quantum many-body systems can spontaneously break discrete time-translation symmetry, realizing discrete time crystals. To date, both experimental and theoretic…

quant-ph2023

Extending the Computational Reach of a Superconducting Qutrit Processor

Noah Goss, Samuele Ferracin, Akel Hashim +5

Quantum computing with qudits is an emerging approach that exploits a larger, more-connected computational space, providing advantages for many applications, including quantum simu…

quant-ph2021

Quantum-tailored machine-learning characterization of a superconducting qubit

Élie Genois, Jonathan A. Gross, Agustin Di Paolo +5

Machine learning (ML) is a promising approach for performing challenging quantum-information tasks such as device characterization, calibration and control. ML models can train dir…

quant-ph2021

Experimental Characterization of Crosstalk Errors with Simultaneous Gate Set Tomography

Kenneth Rudinger, Craig W. Hogle, Ravi K. Naik +11

Crosstalk is a leading source of failure in multiqubit quantum information processors. It can arise from a wide range of disparate physical phenomena, and can introduce subtle corr…

quant-ph2023

Demonstrating scalable randomized benchmarking of universal gate sets

Jordan Hines, Marie Lu, Ravi K. Naik +12

Randomized benchmarking (RB) protocols are the most widely used methods for assessing the performance of quantum gates. However, the existing RB methods either do not scale to many…

physics.ins-det2016

The Phase-Contrast Imaging Instrument at the Matter in Extreme Conditions Endstation at LCLS

Bob Nagler, Andreas Schropp, Eric C. Galtier +13

We describe the Phase-Contrast Imaging instrument at the Matter in Extreme Conditions (MEC) endstation of the Linac Coherent Light Source. The instrument can image phenomena with a…

quant-ph2024

Distributed Architecture for FPGA-based Superconducting Qubit Control

Neelay Fruitwala, Gang Huang, Yilun Xu +6

Quantum circuits utilizing real time feedback techniques (such as active reset and mid-circuit measurement) are a powerful tool for NISQ-era quantum computing. Such techniques are…

quant-ph2021

Randomized compiling for scalable quantum computing on a noisy superconducting quantum processor

Akel Hashim, Ravi K. Naik, Alexis Morvan +11

The successful implementation of algorithms on quantum processors relies on the accurate control of quantum bits (qubits) to perform logic gate operations. In this era of noisy int…

quant-ph2024

AC/DC: Automated Compilation for Dynamic Circuits

Siyuan Niu, Efekan Kokcu, Anupam Mitra +6

Dynamic quantum circuits incorporate mid-circuit measurements and feed-forward operations originally intended to realize Quantum Error Correction. This paradigm has recently been u…

quant-ph2026

Understanding Quantum Instruments

Akel Hashim

The quantum instrument (QI) formalism is required to model mid-circuit measurements (MCMs) and the dependence of the post-measurement state on the measurement outcome. Correctly mo…

quant-ph2026

Advances in Josephson Junction Materials and Processes Toward Practical Quantum Computing

Hyunseong Kim, Gyunghyun Jang, Seungwon Jin +8

The Josephson junction is the fundamental nonlinear building block of superconducting quantum technologies. Its macroscopic quantum tunneling physics underpins superconducting quan…

quant-ph2022

Summary: Chicago Quantum Exchange (CQE) Pulse-level Quantum Control Workshop

Kaitlin N. Smith, Gokul Subramanian Ravi, Thomas Alexander +14

Quantum information processing holds great promise for pushing beyond the current frontiers in computing. Specifically, quantum computation promises to accelerate the solving of ce…

quant-ph2023

A quantum-classical co-processing protocol towards simulating nuclear reactions on contemporary quantum hardware

Francesco Turro, Trevor Chistolini, Akel Hashim +8

Quantum computers hold great promise for arriving at exact simulations of nuclear dynamical processes (e.g., scattering and reactions) that are paramount to the study of nuclear ma…

quant-ph2023

Powerful Quantum Circuit Resizing with Resource Efficient Synthesis

Siyuan Niu, Akel Hashim, Costin Iancu +2

In the noisy intermediate-scale quantum era, mid-circuit measurement and reset operations facilitate novel circuit optimization strategies by reducing a circuit's qubit count in a…

quant-ph2021

Hardware-Efficient Microwave-Activated Tunable Coupling Between Superconducting Qubits

Bradley K. Mitchell, Ravi K. Naik, Alexis Morvan +7

Generating high-fidelity, tunable entanglement between qubits is crucial for realizing gate-based quantum computation. In superconducting circuits, tunable interactions are often i…

quant-ph2025

Heisenberg-limited calibration of entangling gates with robust phase estimation

Kenneth Rudinger, J. P. Marceaux, Akel Hashim +3

The calibration of high-quality two-qubit entangling gates is an essential component in engineering large-scale, fault-tolerant quantum computers. However, many standard calibratio…

quant-ph2025

Hardware-Assisted Parameterized Circuit Execution

Abhi D. Rajagopala, Akel Hashim, Neelay Fruitwala +6

Standard compilers for quantum circuits decompose arbitrary single-qubit gates into a sequence of physical X(pi/2) pulses and virtual-Z phase gates. Consequently, many circuit clas…