Abstract
The physics of interacting integer-spin chains has been a topic of intense theoretical interest, particularly in the context of symmetry-protected topological phases. However, there has not been a controllable model system to study this physics experimentally. We demonstrate how spin-dependent forces on trapped ions can be used to engineer an effective system of interacting spin-1 particles. Our system evolves coherently under an applied spin-1 XY Hamiltonian with tunable, long-range couplings, and all three quantum levels at each site participate in the dynamics. We observe the time evolution of the system and verify its coherence by entangling a pair of effective three-level particles (`qutrits') with 86% fidelity. By adiabatically ramping a global field, we produce ground states of the XY model, and we demonstrate an instance where the ground state cannot be created without breaking the same symmetries that protect the topological Haldane phase. This experimental platform enables future studies of symmetry-protected order in spin-1 systems and their use in quantum applications.
Highlights
By adiabatically ramping a global field, we produce ground states of the XY model, and we demonstrate an instance where the ground state cannot be created without breaking the same symmetries that protect the topological Haldane phase
A major area of current research is devoted to developing experimentally controllable systems that can be used for quantum computation, quantum communication, and quantum simulation of many-body physics
Already with our experimentally implemented Hamiltonian, we find a useful test case where the symmetry of the ground state prevents it from being created via the simple adiabatic protocol described above
Summary
A major area of current research is devoted to developing experimentally controllable systems that can be used for quantum computation, quantum communication, and quantum simulation of many-body physics. It is computationally easy to find the ground-state energy of a spin-1=2 chain with nearestneighbor-only interactions in one dimension; for systems with spin 7=2 or higher, the problem is known to belong to the QMA-complete complexity class, which is a quantum analog of the classical NP-complete class [6,7]. When individual three-level systems are coupled together, they can be used to encode the physics of interacting spin-1 particles Such systems have attracted a great deal of theoretical interest following Haldane’s conjecture that antiferromagnetic Heisenberg spin-1 chains, as opposed to spin-1=2 systems, have a finite energy gap that corresponds to exponentially decaying correlation functions [11,12]. The tools demonstrated here could enable future studies of symmetry-protected order and can be extended to SU(3) models and other systems of higher symmetry [49]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
