Transverse-Field Ising Dynamics in a Rydberg-Dressed Atomic Gas

Abstract

We report on the realization of long-range Ising interactions in a cold gas of cesium atoms by Rydberg dressing. The interactions are enhanced by coupling to Rydberg states in the vicinity of a Förster resonance. We characterize the interactions by measuring the mean-field shift of the clock transition via Ramsey spectroscopy, observing one-axis twisting dynamics. We furthermore emulate a transverse-field Ising model by periodic application of a microwave field and detect dynamical signatures of the paramagnetic-ferromagnetic phase transition. Our results highlight the power of optical addressing for achieving local and dynamical control of interactions, enabling prospects ranging from investigating Floquet quantum criticality to producing tunable-range spin squeezing.

Raman sideband cooling in optical tweezer arrays for Rydberg dressing

“…This so-called Rydberg dressing allows to engineer interactions over long distances among ground state atoms [41][42][43][44]. Coherent dressing induced interactions were realised so far in a pair of microtraps, optical lattices or bulk systems [45][46][47][48], but not in larger optical tweezer arrays. The central challenge is to overcome inhomogeneities of the trapping potentials, which are typically on the order of 10 % of the total trap depth.…”

Monitoring Quantum Simulators via Quantum Nondemolition Couplings to Atomic Clock Qubits

“…In the standard scenario of analog quantum simulation, a broad and tunable class of many-body Hamiltonians of interest is designed based on the resources provided by a particular physical platform. Examples in different physical platforms include spin models realized with Rydberg atoms [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] (for a review, see Ref. [20]), trapped ions [21][22][23] or superconducting qubits [24,25], or Hubbard models realized with bosonic and fermionic atoms in optical lattices [26][27][28].…”

“…Remarkably, as we show in Sec. II, this can be achieved with Rydberg-tweezer platforms [1][2][3][4][5]8,9] using laser-dressing schemes [12][13][14][15][16][17] and by employing a Rydberg-blockade mechanism between the c qubit and the simulator atoms to implement the QND Hamiltonian (1). Second, we wish to explore and illustrate the application of quantum protocols that build on the QND gate described previously, providing access to quantum many-body observables of interest under experimentally realistic conditions.…”

“…Rydberg-tweezer arrays in one, two, and three dimensions [1][2][3][4][5]8,9] provide the tools to design a broad class of spin Hamiltonians H spin via Rydberg dressing [12][13][14][15][16][17]. Here, long-lived atomic (hyperfine) ground states are trapped in the optical tweezer and play the role of the spins in our quantum simulator, while the two-body interactions are engineered by admixing weakly to the ground state via off-resonant laser dressing of the (strong) van der Waals interactions between Rydberg states [43,44].…”

Transition Slow-Down by Rydberg Interaction of Neutral Atoms and a Fast Controlled-not Quantum Gate

“…There are exciting advances in Rydberg atom quantum science recently [1][2][3][4][5][6][7][8] because of the feasibility to coherently and rapidly switch on and off the strong dipoledipole interaction. Such interaction enables simulation of quantum many-body physics [9][10][11][12][13][14][15][16][17][18][19][20][21][22], probing and manipulation of single photons [23][24][25][26][27][28][29][30][31][32][33][34][35], large-scale entanglement generation [36,37], and quantum computation [36][37][38][39][40][41][42][43][44][45][46][47]…”