Two-dimensional and Disordered Superconductors (TIDES)

Liste des Contributions

7. Quantum critical collapse of the pinned vortex glass at the superconductor-insulator transition

Dr Benjamin SACEPE (Institut Néel, CNRS Grenoble)

13/07/2026 09:30

Superconducting films of amorphous indium oxide (a:InO) undergo a transition to an insulating state upon increasing disorder or magnetic field. The gradual suppression of the critical temperature as the disorder-driven transition is approached has long suggested a continuous collapse of the superfluid density, in line with the conventional picture of a continuous quantum phase transition. In...

24. Conference Talk: On the pairing symmetry of moiré graphene superconductors

Mohit Randeria (Ohio State University)

13/07/2026 10:30

Eight years after the discovery of superconductivity in magic-angle twisted bilayer graphene, its pairing symmetry is not definitively established. I will first discuss existing experimental and theoretical constraints on the SC order parameter. I will then focus on Andreev spectroscopy, which is a phase sensitive probe uniquely suited to address this issue. I will describe recent theoretical...

6. Absolute measurement of penetration depth of superconducting thin films using microwave stripline resonators

Pratap Raychaudhuri (Tata Institute of Fundamental Research, Mumbai)

Superconducting microstrip resonators, which leverage kinetic inductance to probe electrodynamics, are sensitive tools for studying superconducting thin films at microwave frequencies. However, extracting the absolute superconducting penetration depth, from these measurements remains challenging. In this work, we present a hybrid method to determine the absolute value of over a wide...

18. Controlling topological superconducting phases in TMD heterostructure

Dganit MEIDAN (SPMS/CentraleSupelec)

Transition metal dichalcogenides (TMDs) offer a highly tunable platform for investigating topological phases and unconventional superconductivity. In this talk, I will focus on hexagonally structured monolayers, where the heavy transition metal and the broken inversion symmetry give rise to Ising spin orbit coupling. I will begin by discussing a topological nodal superconducting phase...

15. Dielectric properties of NbN-films at the insulating side of the superconductor-insulator-transition

Max Reinhart (University of Regensburg)

In 2D strongly disordered thin films the superconductor-insulator-transition (SIT) occurs [1]. The resistive behaviour of the insulating side of this transition is well studied, as it has been observed in various materials [2,3]. For the imaginary part of the impedance the situation is less clear. While it is known, that the superconducting side behaves inductive, we performed experiments on...

11. Disordered superconducting nanoporous films – Model systems to explore BKT physics and quantum phase transitions

Sangita Bose (UM-DAE Centre for Excellence in Basic Sciences)

Conference Talk

19. Disordered superconductivity in boron-doped nanocrystalline diamond

Georgina Klemencic (University of Glasgow)

Boron-doped nanocrystalline diamond (BNCD) is a low-temperature granular superconductor with typical transition temperatures of order 3-5 K and upper critical fields of several tesla [1,2]. The superconductivity develops within a columnar, microstructured material whose superconducting properties are strongly dependent on growth conditions [2-4]. Microwave measurements also show a large sheet...

16. Emergence of gapless superconductivity in annealed molybdenum nitride thin films

Frederik Bolle (University of Stuttgart)

Molybdenum nitride (MoN) is a disordered superconductor, which garnered attention due to its high critical temperature ($\delta$-MoN: $T_c\sim 13\,\text{K}$), robustness in high magnetic fields and short coherence lengths, which allows the deposition of ultra-thin films below 5 nm, a property that is crucial for superconducting detector applications.
Here we report on another interesting...

9. Experimental aspects of 2D superconductivity and topology

Ding Zhang (Tsinghua University)

Superconductivity in highly crystalline 2D materials has become a vibrant field. It not only encompasses emergent quantum phenomena including Ising superconductivity but also helps us deepen the understanding on issues such as quantum phase transitions.

This lecture consists of two parts. In the first part, I will take NbSe2 as an example and review the studies over the decade that are...

5. Inverse melting of the vortex lattice in a-Re6Zr thin films

Pratap Raychaudhuri (Tata Institute of Fundamental Research, Mumbai)

Inverse melting refers to a phenomenon where a liquid transforms into a solid with increase in temperature before melting again at a higher temperature. Predicted more than a century ago, inverse melting is rarely observed. In this talk, I will describe low temperature scanning tunneling spectroscopy experiments on a 20 nm thick amorphous Re6Zr (a-Re6Zr) thin films from which we observe direct...

17. Layer-selective Cooper pairing in an alternately stacked transition metal dichalcogenide

Miguel Ugeda (Donostia International Physics Center (DIPC))

Materials exhibiting multiple superconducting phases are exceptionally rare in nature. The few known examples of multiphase superconductors display complex phase diagrams, where distinct phases can be independently induced by means of external stimuli such as pressure or magnetic fields. Here we report the coexistence of two superconducting condensates with different spatial localization in...

10. Lithium intercalation induces superconductivity with anomalous metal phase, resistance/gap oscillations, and even ferromagnetism

Ding Zhang (Tsinghua University)

Lithium intercalation is a powerful approach to realizing emergent quantum phenomena in a variety of material systems. Here we report our recent studies of lithium intercalated superconductors by utilizing a solid lithium-ion conductor. We transfer exfoliated materials such as TiSe2 [1,2], Bi2Sr2CaCu2O8+x (Bi-2212) [3], and FeSe [4] on this conductor. The exfoliated flakes can be intercalated...

2. Microwave kinetic inductance and phase fluctuation of disordered and granular superconductors

Jan Pusskeiler (1. Physikalisches Institut, University of Stuttgart)

Kinetic inductance $L_\mathrm{kin}$ quantifies the inertia of the superconducting condensate and hence the low-temperature electrodynamics of superconducting microwave circuitry. We directly probe the inductive response in the broadband reactance of superconducting granular aluminum and titanium nitride from MHz to GHz frequencies, $\mathrm{Im}(𝑍) = \omega \cdot L_\mathrm{kin}$, by Corbino...

26. Non-equilibrium quasiparticle dynamics in disordered superconductors after absorption of single photons

Steven de Rooij;de Rooij (Leiden University)

Increasing disorder in a superconductor increases the kinetic inductance. This enables high impedance quantum circuits and sensitive single photon detectors with a high absorption efficiency. These applications are susceptible to quasiparticle excitations. The single photon response in microwave kinetic inductance detectors (MKIDs) is dictated by quasiparticle recombination, and quasiparticles...

20. Percolation and (super)conduction: 2d superconductors with correlated disorder

Giulia Venditti

Two-dimensional superconductors should exhibit a Berezinskii–Kosterlitz–Thouless (BKT) transition, and the 𝑇-dependence of the superfluid stiffness should distinguish between nodal or gapped order parameter symmetries. However, this picture dramatically changes when large scale inhomogeneities and spatially correlated disorder are taken into account, washing out BKT signatures. At the same...

8. Pressure Induced Anomalous Metal in the Vicinity of the Superconductor Insulator Transition

Dr Roy Cohen (Bar Ilan university)

The Superconductor-to-Insulator Transition (SIT) in two-dimensional superconductors occurs due to a competition between superconductivity, quantum interferences, Coulomb interactions, and disorder. Despite extensive theoretical and experimental investigation, the SIT remains an active research area due to the potential for exotic phases near the transition. One such phase is the Anomalous...

21. Recombination of localized quasiparticles in an disordered superconductors probed with resonators

Pieter de Visser;de Visser (SRON / TU Delft, Netherlands)

Disordered superconductors offer new impedance regimes for quantum circuits, enable a pathway to protected qubits, and can improve superconducting detectors due to their high kinetic inductance and sheet resistance. Our focus is on kinetic inductance detectors for visible- to near-infrared wavelengths, for exoplanet research.
The performance of these devices is determined by quasiparticles...

25. Search for spin-triplet superconductivity in van der Waals hybrid systems

Elke Scheer (University of Konstanz)

Hybrid structures combining a superconductor (S) with a magnetically inhomogeneous
material (F) are known to generate long-range, spin-polarized (spin-triplet) Cooper pairs
[1]. The magnetic inhomogeneity at S/F interfaces converts singlet and zero-spin-triplet
Cooper pairs into fully polarized spin-triplet Cooper pairs. Experimental support for this
mechanism has been obtained from...

27. Sub-gap modes observed with Kinetic inductance detectors: source of extra-dissipation in disordered thin superconductors?

Florence LEVY-BERTRAND (CNRS - Institut Néel)

Kinetic inductance detectors (KIDs) are state-of-the-art detectors used for observations in the millimeter-wave range in astrophysics. They are planar resonant circuits consisting of thin superconducting films deposited on an insulating substrate. The photon detection principe consists in monitoring the shift in the resonance frequency, which is proportional to the incident power [1]....

22. Summer School Lecture 1: Introduction to the Superconductor-Insulator Transition

Mohit Randeria (Ohio State University)

This lecture will be a pedagogical introduction to the theory of the disorder-driven superconductor-to-insulator transition in 2D s-wave superconductors, developed over the years with N. Trivedi and collaborators [1-6]. Predictions for and comparisons with experiments will be emphasized. For students who want to do some background reading, I especially recommend reference [3s] and [4].

[1]...

23. Summer School Lecture 2: Are There Bounds on the Superconducting Transition Temperature?

Mohit Randeria (Ohio State University)

The question of understanding limits on the superconducting transition temperature Tc is of great fundamental and technological importance. I will begin with a pedagogical introduction to this question and describe recent progress on deriving rigorous upper bounds [1] on the Tc of 2D superconductors applicable to a wide range of quantum materials and to ultracold atomic gases. I will...

14. Superconductivity in Ni–Bi Bilayer Thin Films: Evidence for Anisotropic Strong-Coupling Pairing

Sulagna Dutta (Tata Institute of Fundamental Research, Mumbai)

We report superconductivity in sputter-deposited Ni–Bi bilayer thin films with varying thicknesses [Bi (40–80 nm)/Ni (5–10 nm)]. While as-deposited films show no superconductivity, post-deposition annealing induces the formation of the intermetallic NiBi3 phase, leading to the emergence of superconductivity. The Bi (80 nm)/Ni (10 nm) film, corresponding closely to NiBi₃ stoichiometry, exhibits...

12. The nature of the “pseudogap” in the insulating phase of highly disordered superconductors

Aviad Frydman (Bar Ilan University, Israel)

Disordered thin films undergoing a superconductor–insulator transition provide a controlled setting for studying pseudogap physics in the absence of competing electronic orders. Although theory predicts that local Cooper pairing can survive deep into the insulating phase, direct spectroscopic confirmation has remained experimentally inaccessible because tunneling measurements in highly...

13. Unveiling Novel Aspects of Superconductivity in Twisted Trilayer Graphene

Mitali Banerjee (Ecole Polytechnique Federal de Lausanne)

Twisted trilayer graphene (TTG) has emerged as a particularly intriguing platform for studying moiré superconductivity. Its flat-band physics closely resembles that of twisted bilayer graphene, yet TTG offers an additional degree of tunability in its band structure, providing a valuable handle for uncovering the mechanisms of moiré superconductivity. In addition, the interference between the...