Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Cost function dependent barren plateaus in shallow parametrized quantum circuits

Journal Article · · Nature Communications
Variational quantum algorithms (VQAs) optimize the parameters θ of a parametrized quantum circuit V(θ) to minimize a cost function C. While VQAs may enable practical applications of noisy quantum computers, they are nevertheless heuristic methods with unproven scaling. Here, we rigorously prove two results, assuming V(θ) is an alternating layered ansatz composed of blocks forming local 2-designs. Our first result states that defining C in terms of global observables leads to exponentially vanishing gradients (i.e., barren plateaus) even when V(θ) is shallow. Hence, several VQAs in the literature must revise their proposed costs. On the other hand, our second result states that defining C with local observables leads to at worst a polynomially vanishing gradient, so long as the depth of V(θ) is Ο(logn). Our results establish a connection between locality and trainability. We illustrate these ideas with large-scale simulations, up to 100 qubits, of a quantum autoencoder implementation.
Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE Laboratory Directed Research and Development (LDRD) Program
Grant/Contract Number:
89233218CNA000001
OSTI ID:
1826512
Report Number(s):
LA-UR--19-32681
Journal Information:
Nature Communications, Journal Name: Nature Communications Journal Issue: 1 Vol. 12; ISSN 2041-1723
Publisher:
Nature Publishing GroupCopyright Statement
Country of Publication:
United States
Language:
English

References (38)

Fermionic Quantum Computation journal May 2002
Integration with Respect to the Haar Measure on Unitary, Orthogonal and Symplectic Group journal March 2006
Local Random Quantum Circuits are Approximate Polynomial-Designs journal August 2016
Quantum Computation and Quantum Information book January 2011
A note on analytic functions in the unit circle journal July 1932
A Comparison of the Bravyi–Kitaev and Jordan–Wigner Transformations for the Quantum Simulation of Quantum Chemistry journal September 2018
Generalized Unitary Coupled Cluster Wave functions for Quantum Computation journal November 2018
Hardware-efficient variational quantum eigensolver for small molecules and quantum magnets journal September 2017
A variational eigenvalue solver on a photonic quantum processor journal July 2014
Barren plateaus in quantum neural network training landscapes journal November 2018
Variational consistent histories as a hybrid algorithm for quantum foundations journal July 2019
Training deep quantum neural networks journal February 2020
Quantum generalisation of feedforward neural networks journal September 2017
IBM Q Experience as a versatile experimental testbed for simulating open quantum systems journal January 2020
Variational quantum unsampling on a quantum photonic processor journal January 2020
Quantum supremacy using a programmable superconducting processor journal October 2019
The theory of variational hybrid quantum-classical algorithms journal February 2016
Noise resilience of variational quantum compiling journal April 2020
Variational-state quantum metrology journal August 2020
RTNI—A symbolic integrator for Haar-random tensor networks journal September 2019
Quantum autoencoders for efficient compression of quantum data journal August 2017
Quantum autoencoders via quantum adders with genetic algorithms journal October 2018
Large gradients via correlation in random parameterized quantum circuits journal January 2021
A Simplex Method for Function Minimization journal January 1965
Quantum singular value decomposer journal June 2020
Exact and approximate unitary 2-designs and their application to fidelity estimation journal July 2009
Variational quantum eigensolver for frustrated quantum systems journal August 2020
Experimental Realization of a Quantum Autoencoder: The Compression of Qutrits via Machine Learning journal February 2019
Coupled-cluster theory in quantum chemistry journal February 2007
Hartree-Fock on a superconducting qubit quantum computer journal August 2020
Quantum Computing in the NISQ era and beyond journal August 2018
Quantum-assisted quantum compiling journal May 2019
An initialization strategy for addressing barren plateaus in parametrized quantum circuits journal December 2019
Variational Quantum Fidelity Estimation journal March 2020
An Adaptive Optimizer for Measurement-Frugal Variational Algorithms journal May 2020
Reachability Deficits in Quantum Approximate Optimization of Graph Problems journal August 2021
Effect of barren plateaus on gradient-free optimization journal October 2021
From the Quantum Approximate Optimization Algorithm to a Quantum Alternating Operator Ansatz journal February 2019

Cited By (9)

Barren plateaus from learning scramblers with local cost functions journal January 2023
The optimization landscape of hybrid quantum–classical algorithms: From quantum control to NISQ applications journal January 2022
The power of quantum neural networks journal June 2021
Adaptive pruning-based optimization of parameterized quantum circuits journal March 2021
Quantum Machine Learning using Gaussian Processes with Performant Quantum Kernels preprint January 2020
Large gradients via correlation in random parameterized quantum circuits text January 2020
Efficient trainability of linear optical modules in quantum optical neural networks text January 2020
Hybrid Classical-Quantum Autoencoder for Anomaly Detection text January 2021
Snowmass White Paper: Quantum Computing Systems and Software for High-energy Physics Research preprint January 2022

Similar Records

Noise-induced barren plateaus in variational quantum algorithms
Journal Article · Sun Nov 28 19:00:00 EST 2021 · Nature Communications · OSTI ID:1832931

Diagnosing Barren Plateaus with Tools from Quantum Optimal Control
Journal Article · Wed Sep 28 20:00:00 EDT 2022 · Quantum · OSTI ID:1891829