TY - JOUR T1 - Multicritical behavior in dissipative Ising models JF - Physical Review A Y1 - 2017 A1 - Vincent R. Overbeck A1 - Mohammad F. Maghrebi A1 - Alexey V. Gorshkov A1 - Hendrik Weimer AB -
We analyze theoretically the many-body dynamics of a dissipative Ising model in a transverse field using a variational approach. We find that the steady state phase diagram is substantially modified compared to its equilibrium counterpart, including the appearance of a multicritical point belonging to a different universality class. Building on our variational analysis, we establish a field-theoretical treatment corresponding to a dissipative variant of a Ginzburg-Landau theory, which allows us to compute the upper critical dimension of the system. Finally, we present a possible experimental realization of the dissipative Ising model using ultracold Rydberg gases.
VL - 95 U4 - 042133 UR - https://journals.aps.org/pra/abstract/10.1103/PhysRevA.95.042133 U5 - doi.org/10.1103/PhysRevA.95.042133 ER - TY - JOUR T1 - Controllable quantum spin glasses with magnetic impurities embedded in quantum solids JF - Physical Review B Y1 - 2013 A1 - Mikhail Lemeshko A1 - Norman Y. Yao A1 - Alexey V. Gorshkov A1 - Hendrik Weimer A1 - Steven D. Bennett A1 - Takamasa Momose A1 - Sarang Gopalakrishnan AB - Magnetic impurities embedded in inert solids can exhibit long coherence times and interact with one another via their intrinsic anisotropic dipolar interaction. We argue that, as a consequence of these properties, disordered ensembles of magnetic impurities provide an effective platform for realizing a controllable, tunable version of the dipolar quantum spin glass seen in LiHo$_x$Y$_{1-x}$F$_4$. Specifically, we propose and analyze a system composed of dysprosium atoms embedded in solid helium. We describe the phase diagram of the system and discuss the realizability and detectability of the quantum spin glass and antiglass phases. VL - 88 UR - http://arxiv.org/abs/1307.1130v1 CP - 1 J1 - Phys. Rev. B U5 - 10.1103/PhysRevB.88.014426 ER - TY - JOUR T1 - Topologically Protected Quantum State Transfer in a Chiral Spin Liquid JF - Nature Communications Y1 - 2013 A1 - Norman Y. Yao A1 - Chris R. Laumann A1 - Alexey V. Gorshkov A1 - Hendrik Weimer A1 - Liang Jiang A1 - J. Ignacio Cirac A1 - Peter Zoller A1 - Mikhail D. Lukin AB - Topology plays a central role in ensuring the robustness of a wide variety of physical phenomena. Notable examples range from the robust current carrying edge states associated with the quantum Hall and the quantum spin Hall effects to proposals involving topologically protected quantum memory and quantum logic operations. Here, we propose and analyze a topologically protected channel for the transfer of quantum states between remote quantum nodes. In our approach, state transfer is mediated by the edge mode of a chiral spin liquid. We demonstrate that the proposed method is intrinsically robust to realistic imperfections associated with disorder and decoherence. Possible experimental implementations and applications to the detection and characterization of spin liquid phases are discussed. VL - 4 U4 - 1585 UR - http://arxiv.org/abs/1110.3788v1 J1 - Nat Comms U5 - 10.1038/ncomms2531 ER -