Search

In superconducting circuits, the nonlinearity of Josephson junctions mediates photon interactions, but they are typically dominated by two-photon processes. Here the authors observe multi-photon interactions in a superconducting circuit with Cooper-pair pairing, revealing a new regime of microwave quantum optics.

DC-powered microwave amplifiers approach the quantum noise limit by using the interaction between microwave radiation and inelastic Cooper-pair tunnelling across a voltage-biased Josephson junction.

The authors study a YbCoIn5/CeCoIn5/YbRhIn5 heterostructure. Using non-reciprocity in the second harmonic transport response, they demonstrate the existence of a specific form of finite-momentum pairing called a helical superconducting state, where the phase of the order parameter is spontaneously spatially modulated.

Supersymmetry and Majorana fermions that are their own antiparticles are both concepts from particle physics that may become testable in condensed-matter systems. The observation of Cooper pairs in a helical Dirac gas brings this goal a step closer.

A diode effect—asymmetric transport depending on its direction—is shown in the proximity-induced superconducting state of a Dirac semimetal.

Precise control over the quantum state of a two-dimensional Fermi gas together with single-particle-resolved fluorescence imaging enables the direct observation of the formation of Cooper pairs at the Fermi surface.

By pushing scanning tunnelling spectroscopy down to millikelvin temperatures, it is now possible to image a heavy fermion superconductor and measure the superconducting gap symmetry, with gap nodes in unexpected momentum-space locations.

Thermoelectricity due to the interplay of the nonlocal Cooper pair splitting and the elastic co-tunneling in normal metal-superconductor-normal metal structure is predicted. Here, the authors observe the non-local Seebeck effect in a graphene-based Cooper pair splitting device.

Controllable detection of singlet and triplet Cooper pair splitting via crossed Andreev reflection is demonstrated in spin-polarized quantum dots on a superconducting nanowire platform with strong spin–orbit coupling.

The standard model describes many aspects of particle physics but mechanisms such as the binding of quarks into hadrons, still remain a mystery. The authors theoretically outline an analogy with the Cooper pairs of a superinsulator to demonstrate that the mechanisms behind the infinite resistance of a superinsulator are analogous to that which confine quarks into hadrons.

Superconducting spintronics has the potential to enhance device functionality by realising spin polarised supercurrents with greater coherence and reduced dissipation. Here, using ferromagnetic resonance, the authors investigate the temperature dependence of the Gilbert damping for the Fe layer of Nb/Fe/Nb and Nb/Cr/Fe/Cr/Nb stacks and the impact superconducting spin triplets have on the spin pumping behaviour.

Floquet engineering is often limited by weak light–matter coupling and heating. Now it is shown that exciton-driven fields in monolayer semiconductors produce stronger, longer-lived Floquet effects and reveal hybridization linked to excitonic phases.

Scanned Josephson tunnelling microscopy is used to image Cooper pair tunnelling from a superconducting microscope tip to the quantum condensate of Bi₂Sr₂CaCu₂O_8+x, thus revealing the spatially modulated density of Cooper pairs predicted from several theories of the cuprate pseudogap phase.

Terahertz microspectroscopic imaging at subgap millielectronvolt energies of a two-dimensional superfluid plasmon in few-layer Bi₂Sr₂CaCu₂O_8+x is demonstrated, allowing the spatial resolution of its deeply subdiffractive terahertz electrodynamics.

Magnetic molecules deposited on a metallic substrate constitute a method to engineer the spin properties of the molecule and has potential application in low-power information storage devices. Here, the authors investigate a superconductor/molecule/normal metal heterostructure and demonstrate spin-ordering and proximity induced superconducting properties at the metallo-molecular interface.

A measurement strategy is described that is able to read out the parity of minimal two-site Kitaev chains in real time, by coupling two Majoranas and resolving their quantum capacitance.

Quarks in the interior of hadrons make up most of ordinary matter, yet their observation is not possible, and their properties can only be probed indirectly. Adopting an analogy between physics of superinsulators and high energy physics, the authors present direct observations of the interior of electric mesons made of Cooper pairs by standard transport measurements.

The authors present experimental evidence of three-dimensional superinsulation in a nanopatterned slab of NbTiN. In the electric Meissner state, they find polar nematic order arising from ferroelectric alignment of short electric strings excited by external electromagnetic fields.

Using torque magnetometry, the thermodynamic signatures of bosonic Landau level transitions are observed in a layered superconductor, owing to the formation of Cooper pairs with finite momentum.

An outstanding question about the iron-based superconductors has been whether or not their magnetic characteristics are dominated by itinerant or localized magnetic moments. Absolute measurements and calculations of the magnetic response of undoped and Ni-doped BaFe₂As₂ indicate the latter.

In high-temperature superconductors, a very low density of states, the pseudogap, exists even above the critical temperature. Here, the authors show that this is also the case for a conventional superconductor, titanium nitride thin films, and that this pseudogap is induced by superconducting fluctuations.

Werner et al. present the results of the 201 Trial, a 12-week randomized, double-blind placebo-controlled phase 2a study of risvodetinib, in patients with early untreated Parkinson’s disease. Risvodetinib was found to be safe and well tolerated.

Johnson et al. link ARIA, a complication of anti-amyloid therapy, to clonal expansion of cytotoxic CD8 + T cells with glycolytic reprogramming and vascular trafficking potential, with implications for biomarker development and risk mitigation.

Chiral superconductors are very rare topological materials. Here, the authors report spontaneous magnetic fields inside the superconducting state and low temperature linear behavior in the superfluid density in LaPt₃P, suggesting a chiral d-wave singlet superconducting state.

The ALICE Collaboration provides details on the microscopic mechanism that ends up creating antideuteron in high-energy proton–proton collisions at the Large Hadron Collider.

The mechanism of high-temperature superconductivity remains a subject of debate. Krasnov et al.describe a technique for measuring the spectra of bosons generated during the formation of Cooper pairs in a cuprate, the results of which suggest that the process is governed by electron–electron interactions.

The dynamical phases of out-of-equilibrium Bardeen–Cooper–Schrieffer superconductors have been simulated using cold atoms levitated inside an optical cavity.

The charge–phase duality in superconductors implies that the well-known SQUID has an analogue based on the interference of fluxons. Such a ‘charge quantum interference device’ (or CQUID) has now been experimentally demonstrated.

Finite momentum superconducting pairing refers to a class of unconventional superconducting states where Cooper pairs acquire a non-zero momentum. Here the authors report a new superconducting state in bulk 4Hb-TaS₂, where magnetic fields induce finite momentum pairing via magnetoelectric coupling.

A series of ⁷⁷Se nuclear magnetic resonance measurements on the electron-doped topological insulator Cu_0.3Bi₂Se₃ reveal a spontaneous breaking of the rotational spin symmetry below its superconducting transition temperature.

Measurements of the superfluid stiffness in twisted trilayer graphene reveal unconventional nodal-gap superconductivity, where the superconducting transition is controlled by phase fluctuations rather than Cooper-pair breaking.

The authors study epitaxial thin films of the pyrochlore-sublattice compound LiTi2O4 by RIXS and ARPES. They observe cooperation between strong electron correlations and strong electron-phonon coupling, giving rise to a mobile polaronic ground state in which charge motion and lattice distortions are coupled.

Vortex dynamics and mutual friction in quantum fluids are intimately connected to the fundamental properties of superfluids. Here, the authors reveal previously unexplored mechanisms underlying the mutual friction coefficients in ultracold Fermi superfluids in the unitary limit, suggesting bound quasiparticles within the vortex core play a significant role.

The impact of local magnetic impurities on superconducting order parameter remains largely unexplored. Here, the authors visualize the effect of different magnetic perturbations on a superconductor, unveiling a rich correlation of the interplay between quantum spins and superconductivity in different spectroscopic regimes.

The nature of the dominant pairing mechanism in some two-dimensional transition metal dichalcogenides is still debated. Here, the authors predict that the Kohn-Luttinger mechanism induces chiral p-wave superconductivity in monolayer NbSe₂.

Examples of materials with non-trivial band topology in the presence of strong electron correlations are rare. Now it is shown that quantum fluctuations near a quantum phase transition can promote topological phases in a heavy-fermion compound.

The authors report superconducting topological surface states (TSS) on MBE-grown Fe(Te,Se) films by high-resolution laser-ARPES. Near the FeTe limit, the surface state disappears due to an electron-correlation-driven topological transition associated with decoherence of the d_xy-orbital-derived bands.