Synopsis: Grounding the Hubbard Model

Researchers propose a step-by-step quantum recipe to find the ground state of models of strongly interacting electrons.

Quantum computing evokes the idea of a general-purpose quantum desktop machine. But a more realistic application may lie in quantum simulation. This involves using one quantum system to simulate another, providing a way to explore problems intractable with classical computers. Dave Wecker from Microsoft Research, Washington, and co-workers propose a step-by-step recipe to determine the otherwise difficult to calculate ground state of models of strongly interacting electrons in solids using quantum simulation. When applied to a real simulator, the recipe may help advance our understanding of strongly correlated materials such as high-temperature superconductors.

The researchers focus their study on the Hubbard model—the simplest model of interacting electrons in a lattice. The model has long been used to describe strongly correlated phenomena in condensed-matter physics. Their recipe, which maps the model’s states of interacting electrons onto the states of a quantum simulator based on interacting qubits, comprises three main steps. First, starting from different initial states, corresponding to different phases of matter, the simulator is smoothly (adiabatically) taken to an approximate ground state. Second, it performs an algorithm to find the true ground state from this approximate state. Third, measurements are made on the simulator to extract information about the ground state, such as particle-particle correlations. This information is used to determine the nature of the ground state. Crucially, the authors describe the complete set of qubits and logic gates needed to implement their approach.

This research is published in Physical Review A.

­–Ana Lopes


Features

More Features »

Announcements

More Announcements »

Subject Areas

Quantum PhysicsCondensed Matter Physics

Previous Synopsis

Biological Physics

Termite Skyscrapers

Read More »

Next Synopsis

Graphene

Graphene Majoranas

Read More »

Related Articles

Synopsis: Chaos from a Chilled Cloud of Atoms
Nonlinear Dynamics

Synopsis: Chaos from a Chilled Cloud of Atoms

A map of chaos emerging in a Bose-Einstein condensate provides a rare glimpse of the behavior in a system of many quantum particles.   Read More »

Synopsis: Reducing Vibrations in Mechanical Beams
Condensed Matter Physics

Synopsis: Reducing Vibrations in Mechanical Beams

A vibrating beam could be cooled to its mechanical ground state by coupling its bending and stretching modes via an electronic defect placed in the beam. Read More »

Viewpoint: A More Efficient Way to Describe Interacting Quantum Particles in 1D
Atomic and Molecular Physics

Viewpoint: A More Efficient Way to Describe Interacting Quantum Particles in 1D

A new method for calculating the time-evolving behavior of interacting quantum particles in one dimension can be used to model experiments that were previously beyond description. Read More »

More Articles