| 1. |
- Ahari, Mostafa Tanhayi, et al.
(författare)
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Partons as unique ground states of quantum Hall parent Hamiltonians : The case of Fibonacci anyons
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 15:2
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Tidskriftsartikel (refereegranskat)abstract
- We present microscopic, multiple Landau level, (frustration-free and positive semi-definite) parent Hamiltonians whose ground states, realizing different quantum Hall fluids, are parton-like and whose excitations display either Abelian or non-Abelian braiding statistics. We prove ground state energy monotonicity theorems for systems with different particle numbers in multiple Landau levels, demonstrate S-duality in the case of toroidal geometry, and establish complete sets of zero modes of special Hamiltonians stabilizing parton-like states, specifically at filling factor ν = 2/3. The emergent Entangled Pauli Principle (EPP), introduced in Phys. Rev. B 98, 161118(R) (2018) and which defines the “DNA” of the quantum Hall fluid, is behind the exact determination of the topological characteristics of the fluid, including charge and braiding statistics of excitations, and effective edge theory descriptions. When the closed-shell condition is satisfied, the densest (i.e., the highest density and lowest total angular momentum) zero-energy mode is a unique parton state. We conjecture that parton-like states generally span the subspace of many-body wave functions with the two-body M-clustering property within any given number of Landau levels, that is, wave functions with Mth-order coincidence plane zeroes and both holomorphic and anti-holomorphic dependence on variables. General arguments are supplemented by rigorous considerations for the M = 3 case of fermions in four Landau levels. For this case, we establish that the zero mode counting can be done by enumerating certain patterns consistent with an underlying EPP. We apply the coherent state approach of Phys. Rev. X 1, 021015 (2011) to show that the elementary (localized) bulk excitations are Fibonacci anyons. This demonstrates that the DNA associated with fractional quantum Hall states encodes all universal properties. Specifically, for parton-like states, we establish a link with tensor network structures of finite bond dimension that emerge via root level entanglement.
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| 2. |
- Baiguera, Stefano, et al.
(författare)
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Conformal Carroll scalars with boosts
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 14:4
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Tidskriftsartikel (refereegranskat)abstract
- We construct two distinct actions for scalar fields that are invariant under local Carroll boosts and Weyl transformations. Conformal Carroll field theories were recently argued to be related to the celestial holography description of asymptotically flat spacetimes. However, only few explicit examples of such theories are known, and they lack local Carroll boost symmetry on a generic curved background. We derive two types of conformal Carroll scalar actions with boost symmetry on a curved background in any dimension and compute their energy-momentum tensors, which are traceless. In the first type of theories, time derivatives dominate and spatial derivatives are suppressed. In the second type, spatial derivatives dominate, and constraints are present to ensure local boost invariance. By integrating out these constraints, we show that the spatial conformal Carroll theories can be reduced to lower-dimensional Euclidean CFTs, which is reminiscent of the embedding space construction.
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| 3. |
- Bhardwaj, Lakshya, et al.
(författare)
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Non-invertible higher-categorical symmetries
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- We sketch a procedure to capture general non-invertible symmetries of a d-dimensional quantum field theory in the data of a higher-category, which captures the local properties of topological defects associated to the symmetries. We also discuss fusions of topological defects, which involve condensations/gaugings of higher-categorical symmetries localized on the worldvolumes of topological defects. Recently some fusions of topological defects were discussed in the literature where the dimension of topological defects seems to jump under fusion. This is not possible in the standard description of higher-categories. We explain that the dimension-changing fusions are understood as higher-morphisms of the higher-category describing the symmetry. We also discuss how a 0-form sub-symmetry of a higher-categorical symmetry can be gauged and describe the higher-categorical symmetry of the theory obtained after gauging. This provides a procedure for constructing non-invertible higher-categorical symmetries starting from invertible higher-form or higher-group symmetries and gauging a 0-form symmetry. We illustrate this procedure by constructing non-invertible 2-categorical symmetries in 4d gauge theories and non-invertible 3-categorical symmetries in 5d and 6d theories. We check some of the results obtained using our approach against the results obtained using a recently proposed approach based on’t Hooft anomalies.
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| 4. |
- Bhardwaj, Lakshya, et al.
(författare)
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Non-invertible symmetry webs
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 15:4
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Tidskriftsartikel (refereegranskat)abstract
- Non-invertible symmetries have by now seen numerous constructions in higher dimensional Quantum Field Theories (QFT). In this paper we provide an in depth study of gauging 0-form symmetries in the presence of non-invertible symmetries. The starting point of our analysis is a theory with G 0-form symmetry, and we propose a description of sequential partial gaugings of sub-symmetries. The gauging implements the theta-symmetry defects of the companion paper [1]. The resulting network of symmetry structures related by this gauging will be called a non-invertible symmetry web. Our formulation makes direct contact with fusion 2-categories, and we uncover numerous interesting structures such as symmetry fractionalization in this categorical setting. The complete symmetry web is derived for several groups G, and we propose extensions to higher dimensions. The highlight of this analysis is the complete categorical symmetry web, including non-invertible symmetries, for 3d pure gauge theories with orthogonal gauge groups and its extension to arbitrary dimensions.
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| 5. |
- Bhardwaj, Lakshya, et al.
(författare)
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Unifying constructions of non-invertible symmetries
- 2023
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Ingår i: SciPost Physics. - : SciPost Foundation. - 2542-4653. ; 15:3
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Tidskriftsartikel (refereegranskat)abstract
- In the past year several constructions of non-invertible symmetries in Quantum Field Theory in d ≥ 3 have appeared. In this paper we provide a unified perspective on these constructions. Central to this framework are so-called theta defects, which generalize the notion of theta-angles, and allow the construction of universal and non-universal topological symmetry defects. We complement this physical analysis by proposing a mathematical framework (based on higher-fusion categories) that converts the physical construction of non-invertible symmetries into a concrete computational scheme.
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| 6. |
- Bissi, Agnese, et al.
(författare)
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Positivity, low twist dominance and CSDR for CFTs
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 14:4
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Tidskriftsartikel (refereegranskat)abstract
- We consider a crossing symmetric dispersion relation (CSDR) for CFT four point correla-tion with identical scalar operators, which is manifestly symmetric under the cross-ratios u, v interchange. This representation has several features in common with the CSDR for quantum field theories. It enables a study of the expansion of the correlation function around u = v = 1/4, which is used in the numerical conformal bootstrap program. We elucidate several remarkable features of the dispersive representation using the four point correlation function of phi 1,2 operators in 2d minimal models as a test-bed. When 1 the dimension of the external scalar operator ( increment sigma) is less than 2 , the CSDR gets con-tribution from only a single tower of global primary operators with the second tower being projected out. We find that there is a notion of low twist dominance (LTD) which, as a function of increment sigma, is maximized near the 2d Ising model as well as the non-unitary Yang-Lee model. The CSDR and LTD further explain positivity of the Taylor expansion coefficients of the correlation function around the crossing symmetric point and lead to universal predictions for specific ratios of these coefficients. These results carry over to the epsilon expansion in 4 - epsilon dimensions. We also conduct a preliminary investigation of geometric function theory ideas, namely the Bieberbach-Rogosinski bounds.
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| 7. |
- Bramberger, Max, et al.
(författare)
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Formation of CuO2 sublattices by suppression of interlattice correlations in tetragonal CuO
- 2023
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Ingår i: SciPost Physics. - 2542-4653. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the tetragonal phase of the binary transition metal oxide CuO (t-CuO) within the context of cellular dynamical mean-field theory. Due to its strong antiferromagnetic correlations and simple structure, analysing the physics of t-CuO is of high interest as it may pave the way towards a more complete understanding of high-temperature superconductivity in hole-doped antiferromagnets. In this work we give a formal justification for the weak-coupling assumption that has previously been made for the interconnected sublattices within a single layer of t-CuO by studying the non-local self-energies of the system. We compute momentum-resolved spectral functions using a Matrix Product State (MPS)-based impurity solver directly on the real axis, which does not require any numerically ill-conditioned analytic continuation. The agreement with photoemission spectroscopy indicates that a single-band Hubbard model is sufficient to capture the material’s low energy physics. We perform calculations on a range of different temperatures, finding two magnetic regimes, for which we identify the driving mechanism behind their respective insulating state. Finally, we show that in the hole-doped regime the sublattice structure of t-CuO has interesting consequences on the symmetry of the superconducting state.
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| 8. |
- Datta, Shouvik, et al.
(författare)
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Marginal quenches and drives in Tomonaga-Luttinger liquids
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 14:5
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Tidskriftsartikel (refereegranskat)abstract
- We study Tomonaga-Luttinger liquids thrown out of equilibrium by marginal deformations in the form of interaction modulations. This is modeled by quenching or periodically driving the Luttinger parameter or, equivalently, the compactification radius of the free boson conformal field theory between two different values. We obtain exact analytical results for the evolution of the Loschmidt echo and observables such as the particle and energy densities. Starting from generic initial states, the quench dynamics are shown to exhibit revivals and temporal orthogonalities. For the periodic drive, we show stability or instability of time-evolved physical quantities dependent on the drive parameters. We also compare the corresponding marginally deformed thermal density matrices by non-perturbatively evaluating their Rényi divergence as a Euclidean quench. All the dynamics are shown to be crucially dependent on the ratio of the Luttinger parameters, which corresponds to the Zamolodchikov distance in the space of marginal deformations. Our setup is equivalently interpreted as the dynamics of the bosonic string upon instantaneous changes of the target-space radius.
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| 9. |
- Day, Isidora Araya, et al.
(författare)
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Pfaffian invariant identifies magnetic obstructed atomic insulators
- 2023
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Ingår i: SciPost Physics. - 2542-4653. ; 15:3
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Tidskriftsartikel (refereegranskat)abstract
- We derive a Z4 topological invariant that extends beyond symmetry eigenvalues and Wilson loops and classifies two-dimensional insulators with a C4T symmetry. To formulate this invariant, we consider an irreducible Brillouin zone and constrain the spectrum of the open Wilson lines that compose its boundary. We fix the gauge ambiguity of the Wilson lines by using the Pfaffian at high symmetry momenta. As a result, we distinguish the four C4T-protected atomic insulators, each of which is adiabatically connected to a different atomic limit. We establish the correspondence between the invariant and the obstructed phases by constructing both the atomic limit Hamiltonians and a C4T-symmetric model that interpolates between them. The phase diagram shows that C4T insulators allow ±1 and 2 changes of the invariant, where the latter is overlooked by symmetry indicators.
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| 10. |
- Del Monte, Fabrizio, et al.
(författare)
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The threefold way to quantum periods : WKB, TBA equations and q-Painlevé
- 2023
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Ingår i: SciPost Physics. - : SCIPOST FOUNDATION. - 2542-4653. ; 15:3
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Tidskriftsartikel (refereegranskat)abstract
- We show that TBA equations defined by the BPS spectrum of 5d N = 1 SU(2) Yang-Mills on S1 x R4 encode the q-Painleve III3 equation. We find a fine-tuned stratum in the physical moduli space of the theory where solutions to TBA equations can be obtained exactly, and verify that they agree with the algebraic solutions to q-Painleve. Switching from the physical moduli space to that of stability conditions, we identify two one-parameter deformations of the fine-tuned stratum, where the general solution of the q-Painleve equation in terms of dual instanton partition functions continues to provide explicit TBA solutions. Motivated by these observations, we propose a further extensions of the range of validity of this correspondence, under a suitable identification of moduli. As further checks of our proposal, we study the behavior of exact WKB quantum periods for the quantum curve of local P1 x P1.
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| 11. |
- Donnay, Laura, et al.
(författare)
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p-forms on the celestial sphere
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- We construct a basis of conformal primary wavefunctions (CPWs) for p-form fields in any dimension, calculating their scalar products and exhibiting the change of basis between conventional plane wave and CPW mode expansions. We also perform the analysis of the associated shadow transforms. For each family of p-form CPWs, we observe the existence of pure gauge wavefunctions of conformal dimension increment = p, while shadow p-forms of this weight are only pure gauge in the critical spacetime dimension value D = 2p + 2. We then provide a systematic technique to obtain the large -r asymptotic limit near .Q based on the method of regions, which naturally takes into account the presence of both ordinary and contact terms on the celestial sphere. In D = 4, this allows us to reformulate in a conformal primary language the links between scalars and dual two-forms.
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| 12. |
- Facio, Jorge I., et al.
(författare)
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Engineering a pure Dirac regime in ZrTe5
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 14:4
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Tidskriftsartikel (refereegranskat)abstract
- Real-world topological semimetals typically exhibit Dirac and Weyl nodes that coexist with trivial Fermi pockets. This tends to mask the physics of the relativistic quasiparti-cles. Using the example of ZrTe5, we show that strain provides a powerful tool for in-situ tuning of the band structure such that all trivial pockets are pushed far away from the Fermi energy, but only for a certain range of Van der Waals gaps. Our results naturally reconcile contradicting reports on the presence or absence of additional pockets in ZrTe5, and provide a clear map of where to find a pure three-dimensional Dirac semimetallic phase in the structural parameter space of the material.
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| 13. |
- Gopalakrishna, Megha, et al.
(författare)
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Photon pumping, photodissociation and dissipation at interplay for the fluorescence of a molecule in a cavity
- 2023
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Ingår i: SciPost Physics. - 2542-4653. ; 15:4
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Tidskriftsartikel (refereegranskat)abstract
- We introduce a model description of a diatomic molecule in an optical cavity, with pump and fluorescent fields, and electron and nuclear motion are treated on equal footing and exactly. The model accounts for several optical response temporal scenarios: A Mollow spectrum hindered by electron correlations, a competition of harmonic generation and molecular dissociation, a dependence of fluorescence on photon pumping rate and dissipation. It is thus a general and flexible template for insight into experiments where quantum photon confinement, leakage, nuclear motion and electronic correlations are at interplay.
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| 14. |
- Marten, Svenja, et al.
(författare)
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Transient superconductivity in three-dimensional Hubbard systems by combining matrix-product states and self-consistent mean-field theory
- 2023
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Ingår i: SciPost Physics. - : SciPost Foundation. - 2542-4653. ; 15:6
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Tidskriftsartikel (refereegranskat)abstract
- We combine matrix-product-state (MPS) and mean-field (MF) methods to model the real-time evolution of a three-dimensional (3D) extended Hubbard system formed from one-dimensional (1D) chains arrayed in parallel with weak coupling in-between them. This approach allows us to treat much larger 3D systems of correlated fermions out-of-equilibrium over a much more extended real-time domain than previous numerical approaches. We deploy this technique to study the evolution of the system as its parameters are tuned from a charge-density wave phase into the superconducting regime, which allows us to investigate the formation of transient non-equilibrium superconductivity. In our ansatz, we use MPS solutions for chains as input for a self-consistent time-dependent MF scheme. In this way, the 3D problem is mapped onto an effective 1D Hamiltonian that allows us to use the MPS efficiently to perform the time evolution, and to measure the BCS order parameter as a function of time. Our results confirm previous findings for purely 1D systems that for such a scenario a transient superconducting state can occur.
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| 15. |
- Minahan, Joseph A., et al.
(författare)
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Seven-dimensional super Yang-Mills at negative coupling
- 2023
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Ingår i: SciPost Physics. - : SCIPOST FOUNDATION. - 2542-4653. ; 14:3
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Tidskriftsartikel (refereegranskat)abstract
- We consider the partition function for Euclidean SU(N) super Yang-Mills on a squashed seven-sphere. We show that the localization locus of the partition function has instanton membrane solutions wrapping the six "fixed" three-spheres on the S7. The ADHM vari-ables of these instantons are fields living on the membrane world volume. We compute their contribution by localizing the resulting three-dimensional supersymmetric field theory. In the round-sphere limit the individual instanton contributions are singular, but the singularities cancel when adding the contributions of all six three-spheres. The full partition function on the S7 is well-defined even when the square of the effective Yang -Mills coupling is negative. We show for an SU(2) gauge theory in this regime that the bare negative tension of the instanton membranes is canceled off by contributions from the instanton partition function, indicating the existence of tensionless membranes. We provide evidence that this phase is distinct from the usual weakly coupled super Yang -Mills and, in fact, is gravitational.
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| 16. |
- Nielsen, Ida Egholm, et al.
(författare)
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Dynamics of parafermionic states in transport measurements
- 2023
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Ingår i: SciPost Physics. - 2542-4653. ; 15:5
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Tidskriftsartikel (refereegranskat)abstract
- Advances in hybrid fractional quantum Hall (FQH)-superconductor platforms pave the way for realisation of parafermionic modes. We analyse signatures of these non-abelian anyons in transport measurements across devices with Z6 parafermions (PFs) coupled to an external electrode. Simulating the dynamics of these open systems by a stochastic quantum jump method, we show that a current readout over sufficiently long times constitutes a projective measurement of the fractional charge shared by two PFs. Interaction of these topological modes with the FQH environment, however, may cause poisoning events affecting this degree of freedom which we model by jump operators that describe incoherent coupling of PFs with FQH edge modes. We analyse how this gives rise to a characteristic three-level telegraph noise in the current, constituting a very strong signature of PFs. We discuss also other forms of poisoning and noise caused by interaction with fractional quasiparticles in the bulk of the Hall system. We conclude our work with an analysis of four-PF devices, in particular on how the PF fusion algebra can be observed in electrical transport experiments.
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| 17. |
- Ortmanns, Lara C., et al.
(författare)
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Solution of master equations by fermionic-duality: Time-dependent charge and heat currents through an interacting quantum dot proximized by a superconductor
- 2023
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Ingår i: SciPost Physics. - 2542-4653. ; 14:5
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Tidskriftsartikel (refereegranskat)abstract
- We analyze the time-dependent solution of master equations by exploiting fermionic duality, a dissipative symmetry applicable to a large class of open systems describing quantum transport. Whereas previous studies mostly exploited duality relations after partially solving the evolution equations, we here systematically exploit the invariance under the fermionic duality mapping from the very beginning when setting up these equations. Moreover, we extend the resulting simplifications -so far applied to the local state evolution- to non-local observables such as transport currents. We showcase the ex-ploitation of fermionic duality for a quantum dot with strong interaction -covering both the repulsive and attractive case- proximized by contact with a large-gap superconduc-tor which is weakly probed by charge and heat currents into a wide-band normal-metal electrode. We derive the complete time-dependent analytical solution of this problem involving non-equilibrium Cooper pair transport, Andreev bound states and strong in-teraction. Additionally exploiting detailed balance we show that even for this relatively complex problem the evolution towards the stationary state can be understood analyti-cally in terms of the stationary state of the system itself via its relation to the stationary state of a dual system with inverted Coulomb interaction, superconducting pairing and applied voltages.
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| 18. |
- Rodgers, Ronnie, et al.
(författare)
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Nodal-antinodal dichotomy from anisotropic quantum critical continua in holographic models
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 14:6
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Tidskriftsartikel (refereegranskat)abstract
- We demonstrate that the absence of stable quasiparticle excitations on parts of the Fermi surface, similar to the "nodal-antinodal dichotomy" in underdoped cuprate su-perconductors, can be reproduced in models of strongly correlated electrons defined via a holographic dual. We show analytically that the anisotropy of the quantum critical continuum, which is a feature of these models, may lead to washing out the quasipar-ticle peak in one direction while leaving it intact in the perpendicular one. The effect relies on the qualitatively different scaling of the self-energy in different directions. Us-ing the explicit example of the anisotropic Q-lattice model, we demonstrate how this effect emerges due to specific features of the near horizon geometry of the black hole in the dual description.
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| 19. |
- Sayyad, Sharareh, et al.
(författare)
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Symmetry-protected exceptional and nodal points in non-Hermitian systems
- 2023
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Ingår i: SciPost Physics. - 2542-4653. ; 15:5
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Tidskriftsartikel (refereegranskat)abstract
- One of the unique features of non-Hermitian (NH) systems is the appearance of NH degeneracies known as exceptional points (EPs). The extensively studied defective EPs occur when the Hamiltonian becomes non-diagonalizable. Aside from this degeneracy, we show that NH systems may host two further types of non-defective degeneracies, namely, non-defective EPs and ordinary (Hermitian) nodal points. The non-defective EPs manifest themselves by i) the diagonalizability of the NH Hamiltonian at these points and ii) the non-diagonalizability of the Hamiltonian along certain intersections of these points, resulting in instabilities in the Jordan decomposition when approaching the points from certain directions. We demonstrate that certain discrete symmetries, namely parity-time, parity-particle-hole, and pseudo-Hermitian symmetry, guarantee the occurrence of both defective and non-defective EPs. We extend this list of symmetries by including the NH time-reversal symmetry in two-band systems. Two-band and four-band models exemplify our findings. Through an example, we further reveal that ordinary nodal points may coexist with defective EPs in NH models when the above symmetries are relaxed.
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| 20. |
- Sayyad, Sharareh, et al.
(författare)
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Symmetry-protected exceptional and nodal points in non-Hermitian systems
- 2023
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Ingår i: SciPost Physics. - : Stichting SciPost. - 2542-4653. ; 15:5
-
Tidskriftsartikel (refereegranskat)abstract
- One of the unique features of non-Hermitian (NH) systems is the appearance of NH degeneracies known as exceptional points (EPs). The extensively studied defective EPs occur when the Hamiltonian becomes non-diagonalizable. Aside from this degeneracy, we show that NH systems may host two further types of non-defective degeneracies, namely, non-defective EPs and ordinary (Hermitian) nodal points. The non-defective EPs manifest themselves by i) the diagonalizability of the NH Hamiltonian at these points and ii) the non-diagonalizability of the Hamiltonian along certain intersections of these points, resulting in instabilities in the Jordan decomposition when approaching the points from certain directions. We demonstrate that certain discrete symmetries, namely parity-time, parity-particle-hole, and pseudo-Hermitian symmetry, guarantee the occurrence of both defective and non-defective EPs. We extend this list of symmetries by including the NH time-reversal symmetry in two-band systems. Two-band and four-band models exemplify our findings. Through an example, we further reveal that ordinary nodal points may coexist with defective EPs in NH models when the above symmetries are relaxed.
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| 21. |
- Thull, Charles
(författare)
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Dualities and loops on squashed S3
- 2023
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Ingår i: SciPost Physics. - : SciPost Foundation. - 2542-4653. ; 15:4
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Tidskriftsartikel (refereegranskat)abstract
- We consider N = 4 supersymmetric gauge theories on the squashed three-sphere with six preserved supercharges. We first discuss how Wilson and vortex loops preserve up to four of the supercharges and we find squashing independence for the expectation values 2 of these 3-BPS loops. We then show how the additional supersymmetries facilitate the analytic matching of partition functions and loop operator expectation values to those in the mirror dual theory, allowing one to lift all the results that were previously established on the round sphere to the squashed sphere. Additionally, on the squashed sphere with four preserved supercharges, we numerically evaluate the partition functions of ABJM and its dual super-Yang-Mills at low ranks of the gauge group. We find matching values of their partition functions, prompting us to conjecture the general equality on the squashed sphere. From the numerics we also observe the squashing dependence of the Lee-Yang zeros and of the non-perturbative corrections to the all order large N expression for the ABJM partition function.
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| 22. |
- Venditti, Giulia, et al.
(författare)
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Phenomenological XXZ model for the competition between superconductivity and charge order in cuprates
- 2023
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Ingår i: SciPost Physics. - 2542-4653. ; 15:6
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Tidskriftsartikel (refereegranskat)abstract
- We argue that there is a special doping point in the phase diagram of cuprates, such that the condensation of holes into a charge-ordered and a superconducting phase are degenerate in energy but with an energy barrier in between. We present Monte Carlo simulations of a phenomenological XXZ model for this problem without and with quenched disorder in two dimensions. While in the clean case charge order and superconductivity are separated by a first-order line which is nearly independent of temperature, in the presence of quenched disorder charge order is fragmented into domains separated by superconducting filaments reminiscent of the supersolid behaviour in 4He. Assuming weak interlayer couplings, the resulting phase diagram of the three-dimensional system is in good agreement with the experiments.
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| 23. |
- Venditti, Giulia, et al.
(författare)
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Superfluid response of two-dimensional filamentary superconductors
- 2023
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Ingår i: SciPost Physics. - 2542-4653. ; 15:6
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Tidskriftsartikel (refereegranskat)abstract
- Different classes of low-dimensional superconducting systems exhibit an inhomogeneous filamentary superconducting condensate whose macroscopic coherence still needs to be fully investigated and understood. Here, we present a thorough analysis of the superfluid response of a prototypical filamentary superconductor embedded in a two-dimensional metallic matrix. By mapping the system into an exactly solvable random impedance network, we show how the dissipative (reactive) response of the system non-trivially depends on both the macroscopic and microscopic characteristics of the metallic (superconducting) fraction. We compare our calculations with resonant microwave transport measurements performed on LaAlO3/SrTiO3 heterostructures over an extended range of temperatures and carrier densities finding that the filamentary character of superconductivity accounts for unusual peculiar features of the experimental data.
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