Date:
Thu, 17/10/201312:00-13:30
Location:
Danciger B building, Seminar room
"Quantum simulations of the ISING Model with trapped Ions: Devil's staircase and arbitrary lattice proposal":
A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent optical dipole forces applied to an ion crystal create long range effective spin-spin interactions and allow the simulation of spin Hamiltonians that possess nontrivial phases and dynamics.
We trap linear chains of 171Yb+ ions in a Paul trap, and constrain the occupation of energy levels to the ground hyper fine clock-states, creating a qubit or pseudo-spin 1/2 system. We proceed to implement spin-spin couplings between two ions using the far detuned Molmer-Sorenson scheme and perform adiabatic quantum simulations of Ising Hamiltonians with long-range couplings.
We then demonstrate our ability to control the sign and relative strength of the interaction between three ions. Using this control, we simulate a frustrated triangular lattice, and for the first time establish an experimental connection between frustration and quantum entanglement. We then scale up our simulation to show phase transitions from paramagnetism to ferromagnetism for nine ions, and to anti-ferromagnetism for sixteen ions. The experimental work culminates with our most complicated Hamiltonian - a long range anti-ferromagnetic Ising interaction between 10 ions with a biasing axial field.
Finally, I will propose a setup by which the approach to quantum simulation utilized in our work can be further extended and improved. It is shown how appropriate design of laser fields can provide for arbitrary multi-dimensional spin-spin interaction graphs even for the case of a linear spatial array of ions. This scheme uses currently existing trap technology and is scalable to levels where classical methods of simulation are currently intractable.
A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent optical dipole forces applied to an ion crystal create long range effective spin-spin interactions and allow the simulation of spin Hamiltonians that possess nontrivial phases and dynamics.
We trap linear chains of 171Yb+ ions in a Paul trap, and constrain the occupation of energy levels to the ground hyper fine clock-states, creating a qubit or pseudo-spin 1/2 system. We proceed to implement spin-spin couplings between two ions using the far detuned Molmer-Sorenson scheme and perform adiabatic quantum simulations of Ising Hamiltonians with long-range couplings.
We then demonstrate our ability to control the sign and relative strength of the interaction between three ions. Using this control, we simulate a frustrated triangular lattice, and for the first time establish an experimental connection between frustration and quantum entanglement. We then scale up our simulation to show phase transitions from paramagnetism to ferromagnetism for nine ions, and to anti-ferromagnetism for sixteen ions. The experimental work culminates with our most complicated Hamiltonian - a long range anti-ferromagnetic Ising interaction between 10 ions with a biasing axial field.
Finally, I will propose a setup by which the approach to quantum simulation utilized in our work can be further extended and improved. It is shown how appropriate design of laser fields can provide for arbitrary multi-dimensional spin-spin interaction graphs even for the case of a linear spatial array of ions. This scheme uses currently existing trap technology and is scalable to levels where classical methods of simulation are currently intractable.