Quantum charge glasses of itinerant fermions with cavity-mediated long-range interactions

Müller, Markus; Strack, Philipp; Sachdev, Subir

doi:10.1103/physreva.86.023604

Cited by 58 publications

(91 citation statements)

References 77 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We believe that our Keldysh approach allows an easier comparison with other equilibrium and non-equilibrium (classical and quantum) systems. While some of the results presented here are actually new, and not just known results re-phrased in a new approach, the full utility of our approach will become clear then computing thermodynamics and critical properties of large, open systems with spatially fluctuating degrees of freedom such as disorder [12,14]. In these correlated quantum many-body situations, Master equation approaches are typically limited to relatively small number of atoms and a recipe to compute disorder-averaged quantities does not seem to exist.…”

Section: Discussionmentioning

confidence: 99%

“…In the future, it will be interesting to apply our approach to dissipative quantum glasses coupled to Markovian (and other) baths such as potentially achievable in multi-mode optical cavities [12][13][14] or circuit QED [58]. It would also be desirable to obtain a more general classification of conditions under which quantum phase transitions of closed systems are turned into thermal phase transitions by dissipation-and perhaps to find counterexamples by engineered dissipation along the lines of Refs.…”

Section: Discussionmentioning

confidence: 99%

“…Due to the interplay of external driving, Hamiltonian dynamics and dissipative processes, the observed Dicke superradiance transitions [1,2] exhibit several properties [4][5][6][7] which are not present in the closed Dicke model [8][9][10][11]. Recently, it was shown that other more interesting quantum many-body phases, such as quantum spin and charge glasses with long-range, random interactions [12][13][14] mediated by multiple photon modes, could potentially be simulated with many-body cavity QED.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Keldysh approach for nonequilibrium phase transitions in quantum optics: Beyond the Dicke model in optical cavities

et al. 2013

Self Cite

View full text Add to dashboard Cite

We investigate non-equilibrium phase transitions for driven atomic ensembles, interacting with a cavity mode, coupled to a Markovian dissipative bath. In the thermodynamic limit and at low-frequencies, we show that the distribution function of the photonic mode is thermal, with an effective temperature set by the atom-photon interaction strength. This behavior characterizes the static and dynamic critical exponents of the associated superradiance transition. Motivated by these considerations, we develop a general Keldysh path integral approach, that allows us to study physically relevant nonlinearities beyond the idealized Dicke model. Using standard diagrammatic techniques, we take into account the leading-order corrections due to the finite number of atoms N. For finite N, the photon mode behaves as a damped, classical non-linear oscillator at finite temperature. For the atoms, we propose a Dicke action that can be solved for any N and correctly captures the atoms' depolarization due to dissipative dephasing.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Keldysh approach for nonequilibrium phase transitions in quantum optics: Beyond the Dicke model in optical cavities

et al. 2013

Self Cite

View full text Add to dashboard Cite

show abstract

“…Above a critical pump strength, the occupation of the cavity mode is stabilized and the bosonic atoms organize into a checkerboard density pattern [12]. Many different proposals have been put forward to realize the self-organization of more complex quantum phases [13] reaching from the Mott-insulator [15] over fermionic phases [16][17][18][19][20] and disordered structures [21][22][23][24] to phases with spin-orbit coupling [25][26][27].…”

mentioning

confidence: 99%

Ultracold Fermions in a Cavity-Induced Artificial Magnetic Field

et al. 2016

View full text Add to dashboard Cite

We show how a fermionic quantum gas in an optical lattice and coupled to the field of an optical cavity can self-organize into a state in which the spontaneously emerging cavity field amplitude induces an artificial magnetic field. The fermions form either a chiral insulator or a chiral liquid carrying edge currents. The feedback mechanism via the cavity field enables robust and fast switching of the edge currents and the cavity output can be employed for non-destructive measurements of the atomic dynamics. The controlled generation of topologically non-trivial quantum phases is of greatest interest since they possess special properties such as extended edge states that can be well protected against destructive environmental effects[1]. Thus, materials with topological non-trivial properties have the prospect to be utilized for quantum devices and quantum computing. Well known are topological insulators with protected edge currents created in quantum Hall devices [2] by strong magnetic fields.For neutral atoms strong artificial magnetic fields can be created [3] which act similarly as magnetic fields for charged particles. Such artificial magnetic fields have been used in quantum gases confined to optical lattices to realize two showcase models of topologically insulating phases, the Hofstadter model in two-dimensions [4][5][6][7] or on a ladder geometry [8] and the Haldane model [9].Yet, the dynamic control and detection of topologically non-trivial quantum states remains a great challenge. In order to overcome this difficulty, in this work the dynamical feedback between atoms and an optical cavity is employed to reach a self-organization of topologically non-trivial phases. One fascinating example for a selforganization of a coupled atom-cavity system has been realized recently by placing a bosonic quantum gas into an optical high-finesse resonator subjected to a perpendicular off-resonant pump beam [10][11][12][13][14]. Above a critical pump strength, the occupation of the cavity mode is stabilized and the bosonic atoms organize into a checkerboard density pattern [12]. Many different proposals have been put forward to realize the self-organization of more complex quantum phases [13] reaching from the Mott-insulator [15] over fermionic phases [16][17][18][19][20] and disordered structures [21][22][23][24] to phases with spin-orbit coupling [25][26][27].In this work, we engineer a direct coupling mechanism of the cavity photons to the tunneling of atoms in an optical lattice. This is achieved using a Raman transition induced by the combination of a transverse pump beam and the cavity field (Fig. 1). The frequencies of the pump beam and the cavity mode are chosen such that the energy transfer is close to the energy offset between neigh- boring lattice sites. The resulting process represents an effective tunneling of the atoms. Due to the running-wave nature of the pump beam, a phase ϕ can be imprinted onto the tunneling of the atoms around a plaquette in the presence of cavity photons. We demonstrate that due t...

show abstract

“…This motivates the realization of dipolar quantum spin glasses in a well-isolated setting with long coherence times. Although there have been proposals to mimic the properties of spin and charge glasses using ultracold atoms coupled to multimode cavities [8][9][10][11] , it is also desirable to naturally realize a spin glass using only bare dipolar interactions. Such a realization would amount to a "quantum simulator" and could shed light on the dynamical properties of quantum glasses 4 .…”

Section: Introductionmentioning

confidence: 99%

Controllable quantum spin glasses with magnetic impurities embedded in quantum solids

et al. 2013

View full text Add to dashboard Cite

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 LiHoxY1−xF4.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.

show abstract

Quantum charge glasses of itinerant fermions with cavity-mediated long-range interactions

Cited by 58 publications

References 77 publications

Keldysh approach for nonequilibrium phase transitions in quantum optics: Beyond the Dicke model in optical cavities

Keldysh approach for nonequilibrium phase transitions in quantum optics: Beyond the Dicke model in optical cavities

Ultracold Fermions in a Cavity-Induced Artificial Magnetic Field

Controllable quantum spin glasses with magnetic impurities embedded in quantum solids

Contact Info

Product

Resources

About