Combinatorics

Physics

Topology (electrical circuits)

Construct (python library)

Mathematics

Topological order

Quantum phase transition

Optics

Statistical physics

Quantum algorithm

Phase transition

String (physics)

Programming language

Theoretical physics

Computer science

Quantum computer

Quantum mechanics

Theoretical computer science

Quantum phases

Quantum

Physical Review Research

Quantum computers promise to perform computations beyond the reach of modern computers with profound implications for scientific research. Due to remarkable technological advances, small scale devices are now becoming available for use. One of the most apparent applications for such a device is the study of complex many-body quantum systems, where classical computers are unable to deal with the generic exponential complexity of quantum states. Even zero-temperature equilibrium phases of matter and the transitions between them have yet to be fully classified, with topologically protected phases presenting major difficulties. We construct and measure a continuously parametrized family of states crossing a symmetry protected topological phase transition on the IBM Q quantum computers. We present two complementary methods for measuring string order parameters that reveal the transition, and additionally analyse the effects of noise in the device using simple error models. The simulation that we perform is easily scalable and is a practical demonstration of the utility of near-term quantum computers for the study of quantum phases of matter and their transitions.

Crossing a topological phase transition with a quantum computer