Welcome to Wes Campbell's Reseach Group at UCLA Physics & Astronomy

Our research uses ultra-cold atoms and molecules to learn about the physical processes that permeate our world.

We are specifically focused on the physics of quantum mechanical systems that involve many-body interactions, where our ability to theoretically describe and numerically simulate the microscopic features is severely limited.

Our approach (shared by others, and known in the field as "quantum simulation") is to use well-controlled samples of atoms and molecules to build tiny, physical emulators of the physics we are investigating.

By utilizing these atoms as microscopic computers that can do the work for us, we hope to be able to pick up where supercomputer simulations become intractable and use our quantum simulators to help us to design and understand new materials, perform demanding computations, and learn about the physical universe.

Latest News

Review of Quantum Simulations

Apr 7, 2021: Trapped atomic ions can be used as quantum simulators of lattice spin models. A new review article (that took us 5 years to write) describes the current state of the art and examines some of the future directions for these devices.



Path to Ultracold Organic Molecules

Mar 26, 2021: Laser cooling can refrigerate samples of gas-phase atoms to a fraction of a mili-deree above absolute zero. Central to this technique is the ability for the cooled species to to scatter many photons without bleaching out, which is generally lacking for molecules. Along with the Alexandrova group UCLA (and others), we have shown how to extend this to molecules with carbon rings by employing a seemingly unrelated conecpt from 1930s chemistry called Hammett parameterization. We hope the insights presented in this paper are just the first in a series of discoveries for how to use the vast library of organic chemistry knowledge to achieve single molecule control at the level of single quantum states.



Sideways

Jan 20, 2021: Along with the Hamilton group at UCLA, we have recently shown how a laser can push a trapped ion prependicular to the laser propagation direction with a sign given by the ion's qubit state. This is a new example of a spin-dependent force, and may be important for achieving high fidelity operations in future quantum computers.



A nuclear puzzle

April 14, 2020: There is currently a four orders of magnitude (10,000x) discrepancy between the measured and theoretical values of the magnetic octupole moment of the 173Yb nucleus. Along with theory collaborator Andrei Derevianko and his group at UNR, we have proposed a new method for measuring this nuclear moment using a trapped 173Yb+ ion. This "electron microscope" should allow us to take one of the most detailed "pictures" of an atomic nucleus ever taken.



New State Preparation and Measurement (SPAM) record for a qubit

April 14, 2020: Using the manufactured isotope 133Ba, Justin and Dave have been able to achieve the highest fidelity for the initialization and readout of any qubit using a trapped 133Ba+ ion. The key to this achievement is the unique atomic and molecular properties of this particular species of atom that give it a good balance of high fidelity operations and ease of use.