745 citations · 4.7k across the 155 of their papers we have counts for
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Quantum critical behavior of diluted quasi-one-dimensional Ising chains
Logan Sowadski, Thomas Vojta
CoNbO is a unique magnetic material. It features bulk three-dimensional magnetic order at low temperatures, but its quantum critical behavior in a magnetic field is well de…
Magnetic field-tuned magnetic order and metamagnetic criticality in non-stoichiometric CeAuBi
Halyna Hodovanets, Hyunsoo Kim, Tristin Metz +9
We present a detailed study of magnetization, resistivity, heat capacity, and X-ray and neutron powder diffraction measurements performed on single crystals of non-stoichiometric C…
Random-strain-induced correlations in materials with intertwined nematic and magnetic orders
W. Joe Meese, Thomas Vojta, Rafael M. Fernandes
Electronic nematicity is rarely observed as an isolated instability of a correlated electron system. Instead, in iron pnictides and in certain cuprates and heavy-fermion materials,…
Signatures of a Quantum Griffiths Phase close to an Electronic Nematic Quantum Phase Transition
Pascal Reiss, David Graf, Amir A. Haghighirad +2
In the vicinity of a quantum critical point, quenched disorder can lead to a quantum Griffiths phase, accompanied by an exotic power-law scaling with a continuously varying dynamic…
Inhomogeneous mean-field approach to collective excitations in disordered interacting bosons
Martin Puschmann, João C. Getelina, José A. Hoyos +1
We develop an inhomogeneous quantum mean-field approach to the behavior of collective excitations across the superfluid-Mott glass quantum phase transition in two dimensions, compl…
Monte Carlo simulations of a disordered superconductor-metal quantum phase transition
Ahmed K. Ibrahim, Thomas Vojta
We investigate the quantum phase transitions of a disordered nanowire from superconducting to metallic behavior by employing extensive Monte Carlo simulations. To this end, we map…
Disorder in quantum many-body systems
Thomas Vojta
Impurities, defects, and other types of imperfections are ubiquitous in realistic quantum many-body systems and essentially unavoidable in solid state materials. Often, such random…
Superfluid density and compressibility at the superfluid-Mott glass transition
Cameron Lerch, Thomas Vojta
Systems of disordered interacting bosons with particle-hole symmetry can undergo a quantum phase transition between the superfluid phase and the Mott glass phase which is a gapless…
Quantum percolation phase transition and magneto-electric dipole glass in hexagonal ferrites
S. E. Rowley, T. Vojta, A. T. Jones +7
Hexagonal ferrites do not only have enormous commercial impact (£2 billion/year in sales) due to applications that include ultra-high density memories, credit card stripes, magneti…
Quantum Griffiths phase inside the ferromagnetic phase of NiV
Ruizhe Wang, Adane Gebretsadik, Sara Ubaid-Kassis +9
We study by means of bulk and local probes the d-metal alloy NiV close to the quantum critical concentration, , where the ferromagnetic transition t…
Evidence for magnetic clusters in NiV close to the quantum critical concentration
R. Wang, S. Ubaid-Kassis, A. Schroeder +7
The d-metal alloy NiV undergoes a quantum phase transition from a ferromagnetic ground state to a paramagnetic ground state as the vanadium concentration is incre…
Strong-randomness phenomena in quantum Ashkin-Teller models
Hatem Barghathi, Fawaz Hrahsheh, José A. Hoyos +2
The -color quantum Ashkin-Teller spin chain is a prototypical model for the study of strong-randomness phenomena at first-order and continuous quantum phase transitions. In this…
Strong-disorder magnetic quantum phase transitions: Status and new developments
Thomas Vojta
This article reviews the unconventional effects of random disorder on magnetic quantum phase transitions, focusing on a number of new experimental and theoretical developments duri…
Strong-randomness infinite-coupling phase in a random quantum spin chain
Fawaz Hrahsheh, Rajesh Narayanan, José A. Hoyos +1
We study the ground-state phase diagram of the Ashkin-Teller random quantum spin chain by means of a generalization of the strong-disorder renormalization group. In addition to the…
Monte-Carlo simulations of the dissipative random transverse-field Ising chain
Manal Al-Ali, Thomas Vojta
We study the influence of Ohmic dissipation on the random transverse-field Ising chain by means of large-scale Monte-Carlo simulations. To this end, we first map the Hamiltonian on…
Modification of smeared phase transitions by spatial disorder correlations
David Nozadze, Christopher Svoboda, Fawaz Hrahsheh +1
Phase transitions in disordered systems can be smeared if rare spatial regions develop true static order while the bulk system is in the disordered phase. Here, we study the effect…
Rounding of a first-order quantum phase transition to a strong-coupling critical point
Fawaz Hrahsheh, José A. Hoyos, Thomas Vojta
We investigate the effects of quenched disorder on first-order quantum phase transitions on the example of the -color quantum Ashkin-Teller model. By means of a strong-disorder…
Percolation transition in quantum Ising and rotor models with sub-Ohmic dissipation
Manal Al-Ali, José A. Hoyos, Thomas Vojta
We investigate the influence of sub-Ohmic dissipation on randomly diluted quantum Ising and rotor models. The dissipation causes the quantum dynamics of sufficiently large percolat…
Quantum Griffiths singularities in ferromagnetic metals
David Nozadze, Thomas Vojta
We present a theory of the quantum Griffiths phases associated with the ferromagnetic quantum phase transition in disordered metals. For Ising spin symmetry, we study the dynamics…
Quantum phase transition of the sub-Ohmic rotor model
Manal Al-Ali, Thomas Vojta
We investigate the behavior of an -component quantum rotor coupled to a bosonic dissipative bath having a sub-Ohmic spectral density with . With increasi…
Non-Fermi liquid transport and "universal" ratios in quantum Griffiths phases
David Nozadze, Thomas Vojta
We use the semi-classical Boltzmann equation to investigate transport properties such as electrical resistivity, thermal resistivity, thermopower, and the Peltier coefficient of di…
Transport properties in antiferromagnetic quantum Griffiths phases
David Nozadze, Thomas Vojta
We study the electrical resistivity in the quantum Griffiths phase associated with the antiferromagnetic quantum phase transition in a metal. The resistivity is calculated by means…
Composition-tuned smeared phase transitions
Fawaz Hrahsheh, David Nozadze, Thomas Vojta
Phase transitions in random systems are smeared if individual spatial regions can order independently of the bulk system. In this paper, we study such smeared phase transitions (bo…
Influence of superohmic dissipation on a disordered quantum critical point
Thomas Vojta, J. A. Hoyos, Priyanka Mohan +1
We investigate the combined influence of quenched randomness and dissipation on a quantum critical point with O(N) order-parameter symmetry. Utilizing a strong-disorder renormaliza…