Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

Improved Simulation of Stabilizer Circuits Scott Aaronson

Summary: Improved Simulation of Stabilizer Circuits
Scott Aaronson
University of California, Berkeley
Daniel Gottesman
Perimeter Institute
The Gottesman-Knill theorem says that a stabilizer circuit--that is, a quantum circuit con-
sisting solely of CNOT, Hadamard, and phase gates--can be simulated efficiently on a classical
computer. This paper improves that theorem in several directions. First, by removing the
need for Gaussian elimination, we make the simulation algorithm much faster at the cost of a
factor-2 increase in the number of bits needed to represent a state. We have implemented the
improved algorithm in a freely-available program called CHP (CNOT-Hadamard-Phase), which
can handle thousands of qubits easily. Second, we show that the problem of simulating stabilizer
circuits is complete for the classical complexity class L, which means that stabilizer circuits
are probably not even universal for classical computation. Third, we give efficient algorithms
for computing the inner product between two stabilizer states, putting any n-qubit stabilizer
circuit into a "canonical form" that requires at most O n2
/ log n gates, and other useful tasks.
Fourth, we extend our simulation algorithm to circuits acting on mixed states, circuits con-
taining a limited number of non-stabilizer gates, and circuits acting on general tensor-product
initial states but containing only a limited number of measurements.


Source: Aaronson, Scott - Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT)


Collections: Physics; Computer Technologies and Information Sciences