Dror Orgad
We calculate the two-point magnetic noise spectrum arising from Gaussian superconducting fluctuations, a quantity directly measurable by spin qubit pairs such as nitrogen vacancy centers in diamond. The analysis utilizes the time-dependent…
We study the phase diagram of a bilayer of antiparallel dipolar excitons with a 1:2 density ratio between the layers, as a function of temperature and density. Using quantum Monte Carlo simulations, we show that such a system supports the…
There is evidence for competition between superconductivity and short-range charge-density wave order in a number of cuprate compounds and especially in YBa$_2$Cu$_3$O$_{6+x}$. Here, we use a non-linear sigma model of such competition to…
Uniaxial pressure provides an efficient approach to control the competition between charge density waves (CDWs) and superconductivity in underdoped YBa$_{2}$Cu$_{3}$O$_{\rm{y}}$. It can enhance the correlation volume of ubiquitous…
We explore the effects of spatial locality on the dynamics of random quantum systems subject to a Markovian noise. To this end, we study a model in which the system Hamiltonian and its couplings to the noise are random matrices whose…
We carry out a sign-problem-free quantum Monte Carlo calculation of a bilayer model with a repulsive intra-layer Hubbard interaction and a ferromagnetic inter-layer interaction. The latter breaks the global $SU(2)$ spin rotational symmetry…
A pair-density wave state has been suggested to exist in underdoped cuprate superconductors, with some supporting experimental evidence emerging over the past few years from scanning tunneling spectroscopy. Several studies have also linked…
We consider the macroscopic transport properties of two-dimensional random binary mixtures with identical spatial distributions of the two phases. Previous studies have obtained exact analytical results for the electrical conductivity of a…
We discuss the decay rates of chaotic quantum systems coupled to noise. We model both the Hamiltonian and the system-noise coupling by random $N \times N$ Hermitian matrices, and study the spectral properties of the resulting Lindblad…
The honeycomb $K-\Gamma$ model is known to have both deconfined spin liquid and confined phases. We study here a confinement transition between the Kitaev spin liquid and a dimerized phase in the limit of strong bond anisotropy. By…
Short-range charge-density wave correlations are ubiquitous in underdoped cuprates. They are largely confined to the copper-oxygen planes and typically oscillate out of phase from one unit cell to the next in the c-direction. Recently, it…
Previous studies have shown that bipartite Hubbard systems with inhomogeneous hopping amplitudes can exhibit higher pair-binding energies than the uniform model. Here we examine whether this result holds for systems with a more generic band…
The electrical Hall conductivities of any anisotropic interacting system with reflection symmetry obey sigma_{xy} = - sigma_{yx}. In contrast, we show that the analogous relation between the transverse thermoelectric Peltier coefficients,…
Recent experiments show that charge-density-wave correlations are prevalent in underdoped cuprate superconductors. The correlations are short ranged at weak magnetic fields but their intensity and spatial extent increase rapidly at low…
Wen's chiral Tomonaga-Luttinger model for the edge of an m-layer quantum Hall system of total filling factor nu=m/(pm +- 1) with even p, is derived as a random-phase approximation of the Chern-Simons theory for these states. The theory…
We study a model of a composite system constructed from a "pairing layer" of disconnected attractive-U Hubbard sites that is coupled by single-particle tunneling, t_perp, to a disordered metallic layer. For small inter-layer tunneling the…
We implement the contractor-renormalization method to study the checkerboard Hubbard model on various finite-size clusters as function of the inter-plaquette hopping t' and the on-site repulsion U at low hole doping. We find that the…
We present an analytical study of diamagnetism and transport in a film with superconducting phase fluctuations, formulated in terms of vortex dynamics within the Debye-H\"uckle approximation. We find that the diamagnetic and Nernst signals…
Experimental evidence for the existence of a fluctuating charge-density wave order in the pseudogap regime of YBa$_2$Cu$_3$O$_{6+x}$ has renewed interest in its interplay with superconductivity. Here, we consider the problem within a…
Coexisting fluctuations towards various ordered states are ubiquitous in strongly correlated electronic systems. In particular, measurements of underdoped cuprate high-temperature superconductors reveal evidence for short range charge order…