A5014820976- Quantum Computing Algorithms and Architecture
- Quantum Information and Cryptography
- Quantum-Dot Cellular Automata
- Quantum and electron transport phenomena
- Cloud Computing and Resource Management
- Low-power high-performance VLSI design
- Cooperative Communication and Network Coding
- Advanced biosensing and bioanalysis techniques
- Quantum many-body systems
- Parallel Computing and Optimization Techniques
- Wireless Communication Security Techniques
- Machine Learning and Algorithms
- Mobile Ad Hoc Networks
- Ferroelectric and Negative Capacitance Devices
- Semiconductor materials and devices
- Computability, Logic, AI Algorithms
- Auction Theory and Applications
- Chaos-based Image/Signal Encryption
- Computational Physics and Python Applications
- Complexity and Algorithms in Graphs
- Optical Network Technologies
- Matrix Theory and Algorithms
- Cryptography and Data Security
- Advanced Topics in Algebra
- Coding theory and cryptography
Alibaba Group (United States)
2018-2024
Bellevue Hospital Center
2018-2024
University of Michigan
2015-2020
Tsinghua University
2015
Quantum simulation of chemistry and materials is predicted to be an important application for both near-term fault-tolerant quantum devices. However, at present, developing studying algorithms these problems can difficult due the prohibitive amount domain knowledge required in area algorithms. To help bridge this gap open field more researchers, we have developed OpenFermion software package (www.openfermion.org). open-source library written largely Python under Apache 2.0 license, aimed...
Superconducting qubits provide a promising path toward building large-scale quantum computers. The simple and robust transmon qubit has been the leading platform, achieving multiple milestones. However, fault-tolerant computing calls for operations at error rates significantly lower than those exhibited in state of art. Consequently, alternative superconducting with better protection have attracted increasing interest. Among them, fluxonium is particularly candidate, featuring large...
We introduce a distributed classical simulation algorithm for general quantum circuits, and present numerical results calculating the output probabilities of universal random circuits. find that we can simulate more qubits to greater depth than previously reported using cluster supported by Data Infrastructure Search Technology Division Alibaba Group. For example, computing single amplitude an $8\times 8$ qubit circuit with $40$ was beyond reach supercomputers. Our compute this within $2$...
It is believed that random quantum circuits are difficult to simulate classically. These have been used demonstrate supremacy: the execution of a computational task on computer infeasible for any classical computer. The underlying assertion supremacy by Arute et al. (Nature, 574, 505--510 (2019)) was initially estimated require Summit, world's most powerful supercomputer today, approximately 10,000 years. same performed Sycamore processor in only 200 seconds. In this work, we present tensor...
A quantum instruction set is where hardware and software meet. We develop characterization compilation techniques for non-Clifford gates to accurately evaluate its designs. Applying these our fluxonium processor, we show that replacing the iSWAP gate by square root SQiSW leads a significant performance boost at almost no cost. More precisely, on measure fidelity of up 99.72% averaging 99.31%, realize Haar random two-qubit with an average 96.38%. This error reduction 41% former 50% latter...
Abstract We develop an algorithmic framework for contracting tensor networks and demonstrate its power by classically simulating quantum computation of sizes previously deemed out reach. Our main contribution, index slicing, is a method that efficiently parallelizes the contraction breaking it down into much smaller identically structured subtasks, which can then be executed in parallel without dependencies. benchmark our algorithm on class random circuits, achieving greater than 10 5 times...
We describe an algorithm for finding angle sequences in quantum signal processing, with a novel component we call halving based on new algebraic uniqueness theorem, and another capitalization. present both theoretical experimental results that demonstrate the performance of algorithm. In particular, these two algorithmic ideas allow us to find more than 3000 angles within 5 minutes important applications such as Hamiltonian simulation, all standard double precision arithmetic. This is native...
The design and architecture of a quantum instruction set are paramount to the performance computer. This work introduces gate scheme for qubits with XX + YY coupling that directly efficiently realizes any two-qubit up single-qubit gates. First, this enables high-fidelity execution operations, especially when decoherence is primary error source. Second, since spans entire SU(4) group gates, we can use it attain optimal count algorithm implementation. These two advantages in synergy give rise...
A function computation problem over a directed acyclic network has been considered in the literature, where sink node is required to compute target correctly with inputs arbitrarily generated at multiple source nodes. The links are error free but capacity limited, and intermediate nodes perform coding. computing rate of code average number times that computed for one use network, i.e., each link used most once. In existing papers, two cut-set bounds were proposed on rate. However, we this...
We report our work on the Alibaba Cloud Quantum Development Platform (AC-QDP). The capability of AC-QDP's computational engine was already reported in \cite{CZH+18, ZHN+19}.In this follow-up article, we demonstrate with figures how AC-QDP helps testing large-scale quantum algorithms (currently within QAOA framework). give new benchmark results regular graphs. framework can simulate thousands qubits for up to $4$ layers. Then discuss two interesting use cases have implemented platform: 1....
Randomized benchmarking (RB) is the gold standard for experimentally evaluating quality of quantum operations. The current framework RB centered on groups and their representations, but this can be problematic. For example, Clifford circuits need up to $O(n^2)$ gates, thus cannot scale larger devices. Attempts remedy include new schemes such as linear cross-entropy (XEB), cycle benchmarking, non-uniform RB, they do not fall within group-based framework. In work, we formulate \emph{universal...
We consider the problem of classical strong (amplitude-wise) simulation n-qubit quantum circuits, and identify a subclass simulators we call monotone. This encompasses almost all prominent techniques. prove an unconditional (i.e. without relying on any complexity-theoretic assumptions) explicit (n - 2)(2n <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> 1) lower bound running time within this subclass. Assuming Strong Exponential Time...
Applying phase shifts to qubit drives is known give essentially perfect $Z$ rotations, but the current scheme only compatible with a very special class of two-qubit gates. This puts unnecessary restrictions on quantum instruction set. A proposed arbitrary gates and also uniquely optimal in number pulses needed.
We consider the problem of strong (amplitude-wise) simulation $n$-qubit quantum circuits, and identify a subclass simulators we call monotone. This encompasses almost all prominent techniques. prove an unconditional (i.e. without relying on any complexity theoretic assumptions) explicit $(n-2)(2^{n-3}-1)$ lower bound running time within this subclass. Assuming Strong Exponential Time Hypothesis (SETH), further remark that universal simulator computing amplitude to precision $2^{-n}/2$ must...
Function computation in directed acyclic networks is considered, where a sink node wants to compute target function with the inputs generated at multiple source nodes. The network links are error-free but capacity-limited, and intermediate nodes perform coding. required be computed zero error. computing rate of code measured by average number times that can for one use network. We propose cut-set bound on using an equivalence relation associated function. Our holds general functions...
We report, in a sequence of notes, our work on the Alibaba Cloud Quantum Development Platform (AC-QDP). AC-QDP provides set tools for aiding development both quantum computing algorithms and processors, is powered by large-scale classical simulator deployed Cloud. In this note, we simulate distance-3 logical qubit encoded 17-qubit surface code using experimental noise parameters transmon qubits planar circuit QED architecture. Our simulation features crosstalk induced ZZ-interactions. show...
With the advent of quantum processors exceeding 100 qubits and high engineering complexities involved, there is a need for holistically benchmarking processor to have quality assurance. Linear cross-entropy (XEB) has been used extensively systems with 50 or more but fundamentally limited in scale due exponentially large computational resources required classical simulation. In this work we propose conducting linear XEB random Clifford circuits constant logarithmic depth, scheme call XEB....
We investigate Clifford+$T$ quantum circuits with a small number of $T$-gates. Using the sparsification lemma, we identify time complexity lower bounds in terms $T$-gate count below which strong simulator would improve on state-of-the-art $3$-SAT solving.
We report, in a sequence of notes, our work on the Alibaba Cloud Quantum Development Platform(AC-QDP). AC-QDP provides set tools for aiding development both quantum computing algorithms and processors, is powered by large-scale classical simulator deployed Cloud. In this note, we report computational experiments demonstrating simulation capability AC-QDP. use as benchmark random circuits designed Google's Bristlecone QPU {\cite{GRCS}}. simulate Bristlecone-70 with depth $1 + 32 1$ $0.43$...
Errors are common issues in quantum computing platforms, among which leakage is one of the most-challenging to address. This because leakage, i.e., loss information stored computational subspace undesired subspaces a larger Hilbert space, more difficult detect and correct than errors that preserve subspace. As result, presents significant obstacle development fault-tolerant computation. In this paper, we propose an efficient accurate benchmarking framework called randomized (LRB), for...
We give an arbitrary single-qubit gate compilation scheme on superconducting processors that takes advantage of tuning the phase shift microwave pulses to obtain a continuous set. This is compatible with any two-qubit gate, and we only need calibrate $X_π$ $X_{π/2}$ pulses. implement this fluxonium state-of-the-art fidelities. two other schemes: first requires one pulse variable rotation angle, second four also find if can do virtual $Z$ gates, then gates around axis. Our results apply...