K. Dehmelt, M. Della Pietra, H. Muller, S. E. Tzamarias, A. White, S. White, Z. Zhang, M. Alviggi, I. Angelis, S. Aune, J. Bortfeldt, M. Bregant, F. Brunbauer, M. T. Camerlingo, V. Canale, V. D'Amico, D. Desforge, C. Di Donato, R. Di Nardo, G. Fanourakis, K. J. Floethner, M. Gallinaro, F. Garcia, I. Giomataris, K. Gnanvo, T. Gustavsson, R. Hall-Wilton, P. Iengo, F. J. Iguaz, M. Iodice, D. Janssens, A. Kallitsopoulou, M. Kebbiri, K. Kordas, C. Lampoudis, P. Legou, M. Lisowska, J. Liu, M. Lupberger, S. Malace, I. Maniatis, I. Manthos, Y. Meng, H. Natal da Luz, E. Oliveri, G. Orlandini, T. Papaevangelou, K. Paraschou, F. Petrucci, D. Pfeiffer, M. Pomorski, S. Popescu, F. Resnati, L. Ropelewski, A. Rusu, D. Sampsonidis, L. Scharenberg, T. Schneider, G. Sekhniaidze, M. Sessa, M. Shao, L. Sohl, J. Toledo-Alarcon, A. Tsiamis, Y. Tsipolitis, A. Utrobicic, M. van Stenis, R. Veenhof, X. Wang, Y. Zhou
This paper will review the origins, development, and examples of new versions of Micro-Pattern Gas Detectors. The goal for MPGD development was the creation of detectors that could cost-effectively cover large areas while offering excellent position and timing resolution, and the ability to operate at high incident particle rates. The early MPGD developments culminated in the formation of the RD51 collaboration which has become the critical organization for the promotion of MPGDs and all aspects of their production, characterization, simulation, and uses in an expanding array of experimental configurations. For the Snowmass 2021 study, a number of Letters of Interest were received that illustrate ongoing developments and expansion of the use of MPGDs. In this paper, we highlight high precision timing, high rate application, trigger capability expansion of the SRS readout system, and a structure designed for low ion backflow.
T. Neumann, T. Schneider, A. A. Serga, B. Hillebrands
Brillouin light scattering spectroscopy is a powerful technique which incorporates several extensions such as space-, time-, phase- and wave-vector resolution. Here, we report on the improvement of the wave-vector resolution by including an electro-optical modulator. This provides a reference to calibrate the position of the diaphragm hole which is used for wave-vector selection. The accuracy of this calibration is only limited by the accuracy of the wave-vector measurement itself. To demonstrate the validity of the approach the wave vectors of dipole-dominated spin waves excited by a microstrip antenna were measured.
M. Anelli, R. AntunesNobrega, G. Auriemma, W. Baldini, G. Bencivenni, R. Berutti, V. Bocci, N. Bondar, W. Bonivento, B. Botchin, S. Cadeddu, P. Campana, G. Carbonih, A. Cardini, M. Carletti, P. Ciambrone, E. Dane, S. DeCapua, C. Deplano, P. DeSimone, F. Dettori, A. Falabella, F. Ferreira Rodriguez, M. Frosini, S. Furcas, G. Graziani, L. Gruber, A. Kashchuk, A. Lai, G. Lanfranchi, M. Lenzi, O. Levitskaya, K. Mair, O. Maev, G. Manca, G. Martellotti, A. Massafferri Rodrigues, R. Messi, F. Murtas, P. Neustroev, R. G. C. Oldemane, M. Palutan, G. Passaleva, G. Penso, A. Petrella, D. Pinci, S. Pozzi, G. Sabatino, B. Saitta, R. Santacesaria, E. Santovetti, A. Saputi, A. Sarti, C. Satriano, A. Satta, M. Savrie, B. Schmidt, T. Schneider, A. Sciubba, P. Shatalov, S. Vecchi, M. Veltri, S. Volkov, A. Vorobyev
The LHCb Muon system performance is presented using cosmic ray events collected in 2009. These events allowed to test and optimize the detector configuration before the LHC start. The space and time alignment and the measurement of chamber efficiency, time resolution and cluster size are described in detail. The results are in agreement with the expected detector performance.
F. J. Iguaz, J. Bortfeldt, F. Brunbauer, C. David, D. Desforge, G. Fanourakis, J. Franchi, M. Gallinaro, F. García, I. Giomataris, D. González-Díaz, T. Gustavsson, C. Guyot, M. Kebbiri, P. Legou, J. Liu, M. Lupberger, O. Maillard, I. Manthos, H. Müller, V. Niaouris, E. Oliveri, T. Papaevangelou, K. Paraschou, M. Pomorski, B. Qi, F. Resnati, L. Ropelewski, D. Sampsonidis, T. Schneider, P. Schwemling, L. Sohl, M. van Stenis, P. Thuiner, Y. Tsipolitis, S. E. Tzamarias, R. Veenhof, X. Wang, S. White, Z. Zhang, Y. Zhou
The PICOSEC detection concept consists in a "two-stage" Micromegas detector coupled to a Cherenkov radiator and equipped with a photocathode. A proof of concept has already been tested: a single-photoelectron response of 76 ps has been measured with a femtosecond UV laser at CEA/IRAMIS, while a time resolution of 24 ps with a mean yield of 10.4 photoelectrons has been measured for 150 GeV muons at the CERN SPS H4 secondary line. This work will present the main results of this prototype and the performance of the different detector configurations tested in 2016-18 beam campaigns: readouts (bulk, resistive, multipad) and photocathodes (metallic+CsI, pure metallic, diamond). Finally, the prospects for building a demonstrator based on PICOSEC detection concept for future experiments will be discussed. In particular, the scaling strategies for a large area coverage with a multichannel readout plane, the R\&D on solid converters for building a robust photocathode and the different resistive configurations for a robust readout.
R. A. Gallardo, D. Cortés-Ortuño, T. Schneider, A. Roldán-Molina, Fusheng Ma, R. E. Troncoso, K. Lenz, H. Fangohr, J. Lindner, P. Landeros
Periodically patterned metamaterials are known for exhibiting wave properties similar to the ones observed in electronic band structures in crystal lattices. In particular, periodic ferromagnetic materials are characterized by the presence of bands and bandgaps in their spin-wave spectrum at tunable GHz frequencies. Recently, the fabrication of magnets hosting Dzyaloshinskii-Moriya interactions has been pursued with high interest since properties such as the stabilization of chiral spin textures and nonreciprocal spin-wave propagation emerge from this antisymmetric exchange coupling. In this context, to further engineer the magnon band structure, we propose the implementation of magnonic crystals with periodic Dzyaloshinskii-Moriya interactions, which can be obtained, for instance, via patterning of periodic arrays of heavy-metals wires on top of an ultrathin magnetic film. We demonstrate through theoretical calculations and micromagnetic simulations that such systems show an unusual evolution of the standing spin waves around the gaps in areas of the film that are in contact with the heavy-metal wires. We also predict the emergence of indirect gaps and flat bands and, effects that depend on the strength of the Dzyaloshinskii-Moriya interaction. This study opens new routes towards engineered metamaterials for spin-wave-based devices.
V. Sluka, T. Schneider, R. A. Gallardo, A. Kakay, M. Weigand, T. Warnatz, R. Mattheis, A. Roldan-Molina, P. Landeros, V. Tiberkevich, A. Slavin, G. Schütz, A. Erbe, A. Deac, J. Lindner, J. Raabe, J. Fassbender, S. Wintz
Spin waves offer intriguing novel perspectives for computing and signal processing, since their damping can be lower than the Ohmic losses in conventional CMOS circuits. For controlling the spatial extent and propagation of spin waves on the actual chip, magnetic domain walls show considerable potential as magnonic waveguides. However, low-loss guidance of spin waves with nanoscale wavelengths, in particular around angled tracks, remains to be shown. Here we experimentally demonstrate that such advanced control of propagating spin waves can be obtained using natural features of magnetic order in an interlayer exchange-coupled, anisotropic ferromagnetic bilayer. Using Scanning Transmission X-Ray Microscopy, we image generation of spin waves and their propagation across distances exceeding multiple times the wavelength, in extended planar geometries as well as along one-dimensional domain walls, which can be straight and curved. The observed range of wavelengths is between 1 μm and 150 nm, at corresponding excitation frequencies from 250 MHz to 3 GHz. Our results show routes towards practical implementation of magnonic waveguides employing domain walls in future spin wave logic and computational circuits.
J. Bauche, B. Biskup, M. Cascella, J. Chappell, N. Chritin, D. Cooke, L. Deacon, Q. Deliege, I. Gorgisyan, J. Hansen, S. Jolly, F. Keeble, P. La Penna, S. Mazzoni, D. Medina Godoy, A. Petrenko, M. Quattri, T. Schneider, P. Sherwood, A. Vorozhtsov, M. Wing
A magnetic spectrometer has been developed for the AWAKE experiment at CERN in order to measure the energy distribution of bunches of electrons accelerated in wakefields generated by proton bunches in plasma. AWAKE is a proof-of-principle experiment for proton-driven plasma wakefield acceleration, using proton bunches from the SPS. Electron bunches are accelerated to $\mathcal{O}$(1 GeV) in a rubidium plasma cell and then separated from the proton bunches via a dipole magnet. The dipole magnet also induces an energy-dependent spatial horizontal spread on the electron bunch which then impacts on a scintillator screen. The scintillation photons emitted are transported via three highly-reflective mirrors to an intensified CCD camera, housed in a dark room, which passes the images to the CERN controls system for storage and further analysis. Given the known magnetic field and determination of the efficiencies of the system, the spatial spread of the scintillation photons can be converted to an electron energy distribution. A lamp attached on a rail in front of the scintillator is used to calibrate the optical system, with calibration of the scintillator screen's response to electrons carried out at the CLEAR facility at CERN. In this article, the design of the AWAKE spectrometer is presented, along with the calibrations carried out and expected performance such that the energy distribution of accelerated electrons can be measured.
J. Bortfeldt, F. Brunbauer, C. David, D. Desforge, G. Fanourakis, M. Gallinaro, F. García, I. Giomataris, T. Gustavsson, F. J. Iguaz, M. Kebbiri, K. Kordas, C. Lampoudis, P. Legou, M. Lisowska, J. Liu, M. Lupberger, O. Maillard, I. Manthos, H. Müller, V. Niaouris, E. Oliveri, T . Papaevangelou, K. Paraschou, M. Pomorski, B. Qi, F. Resnati, L. Ropelewski, D. Sampsonidis, L. Scharenberg, T. Schneider, L. Sohl, M. van Stenis, Y. Tsipolitis, S. E. Tzamarias, A. Utrobicic, R. Veenhof, X. Wang, S. White, Z. Zhang, Y. Zhou
The PICOSEC Micromegas detector can time the arrival of Minimum Ionizing Particles with a sub-25 ps precision. A very good timing resolution in detecting single photons is also demonstrated in laser beams. The PICOSEC timing resolution is determined mainly by the drift field. The arrival time of the signal and the timing resolution vary with the size of the pulse amplitude. Detailed simulations based on GARFIELD++ reproduce the experimental PICOSEC timing characteristics. This agreement is exploited to identify the microscopic physical variables, which determine the observed timing properties. In these studies, several counter-intuitive observations are made for the behavior of such microscopic variables. In order to gain insight on the main physical mechanisms causing the observed behavior, a phenomenological model is constructed and presented. The model is based on a simple mechanism of "time-gain per interaction" and it employs a statistical description of the avalanche evolution. It describes quantitatively the dynamical and statistical properties of the microscopic quantities, which determine the PICOSEC timing characteristics, in excellent agreement with the simulations. In parallel, it offers phenomenological explanations for the behavior of these microscopic variables. The formulae expressing this model can be used as a tool for fast and reliable predictions, provided that the input parameter values (e.g. drift velocities) are known for the considered operating conditions.
S. Aune, J. Bortfeldt, F. Brunbauer, C. David, D. Desforge, G. Fanourakis, M. Gallinaro, F. García, I. Giomataris, T. Gustavsson, F. J. Iguaz, M. Kebbiri, K. Kordas, C. Lampoudis, P. Legou, M. Lisowska, J. Liu, M. Lupberger, O. Maillard, I. Manthos, H. Müller, E. Oliveri, T. Papaevangelou, K. Paraschou, M. Pomorski, B. Qi, F. Resnati, L. Ropelewski, D. Sampsonidis, L. Scharenberg, T. Schneider, L. Sohl, M. van Stenis, A. Tsiamis, Y. Tsipolitis, S. E. Tzamarias, A. Utrobicic, R. Veenhof, X. Wang, S. White, Z. Zhang, Y. Zhou
The multi-pad PICOSEC-Micromegas is an improved detector prototype with a segmented anode, consisting of 19 hexagonal pads. Detailed studies are performed with data collected in a muon beam over four representative pads. We demonstrate that such a device, scalable to a larger area, provides excellent time resolution and detection efficiency. As expected from earlier single-cell device studies, we measure a time resolution of approximately 25 picoseconds for charged particles hitting near the anode pad centers, and up to 30 picoseconds at the pad edges. Here, we study in detail the effect of drift gap thickness non-uniformity on the timing performance and evaluate impact position based corrections to obtain a uniform timing response over the full detector coverage.
L. Anderlini, M. Anelli, F. Archilli, G. Auriemma, W. Baldini, G. Bencivenni, A. Bizzeti, V. Bocci, N. Bondar, W. Bonivento, B. Bochin, C. Bozzi, D. Brundu, S. Cadeddu, P. Campana, G. Carboni, A. Cardini, M. Carletti, L. Casu, A. Chubykin, P. Ciambrone, E. Dané, P. De Simone, A. Falabella, G. Felici, M. Fiore, M. Fontana, P. Fresch, E. Furfaro, G. Graziani, A. Kashchuk, S. Kotriakhova, A. Lai, G. Lanfranchi, A. Loi, O. Maev, G. Manca, G. Martellotti, P. Neustroev, R. G. C. Oldeman, M. Palutan, G. Passaleva, G. Penso, D. Pinci, E. Polycarpo, B. Saitta, R. Santacesaria, M. Santimaria, E. Santovetti, A. Saputi, A. Sarti, C. Satriano, A. Satta, B. Schmidt, T. Schneider, B. Sciascia, A. Sciubba, B. G. Siddi, G. Tellarini, C. Vacca, R. Vazquez-Gomez, S. Vecchi, M. Veltri, A. Vorobyev
A method is described which allows to deduce the dead-time of the front-end electronics of the LHCb muon detector from a series of measurements performed at different luminosities at a bunch-crossing rate of 20 MHz. The measured values of the dead-time range from 70 ns to 100 ns. These results allow to estimate the performance of the muon detector at the future bunch-crossing rate of 40 MHz and at higher luminosity.
N. Adachi, V. Adamovitch, Y. Adjovi, K. Aida, H. Akamatsu, S. Akiyama, A. Akli, A. Ando, T. Andrault, H. Antonietti, S. Anzai, G. Arkoun, C. Avenoso, D. Ayrault, M. Banasiewicz, M. Banaśkiewicz, L. Bernandini, E. Bernard, E. Berthet, M. Blanchard, D. Boreyko, K. Boros, S. Charron, P. Cornette, K. Czerkas, M. Dameron, I. Date, M. De Pontbriand, F. Demangeau, Ł. Dobaczewski, L. Dobrzyński, A. Ducouret, M. Dziedzic, A. Ecalle, V. Edon, K. Endo, T. Endo, Y. Endo, D. Etryk, M. Fabiszewska, S. Fang, D. Fauchier, F. Felici, Y. Fujiwara, C. Gardais, W. Gaul, L. Guérin, R. Hakoda, I. Hamamatsu, K. Handa, H. Haneda, T. Hara, M. Hashimoto, T. Hashimoto, K. Hashimoto, D. Hata, M. Hattori, R. Hayano, R. Hayashi, H. Higasi, M. Hiruta, A. Honda, Y. Horikawa, H. Horiuchi, Y. Hozumi, M. Ide, S. Ihara, T. Ikoma, Y. Inohara, M. Itazu, A. Ito, J. Janvrin, I. Jout, H. Kanda, G. Kanemori, M. Kanno, N. Kanomata, T. Kato, S. Kato, J. Katsu, Y. Kawasaki, K. Kikuchi, P. Kilian, N. Kimura, M. Kiya, M. Klepuszewski, E. Kluchnikov, Y. Kodama, R. Kokubun, F. Konishi, A. Konno, V. Kontsevoy, A. Koori, A. Koutaka, A. Kowol, Y. Koyama, M. Kozioł, M. Kozue, O. Kravtchenko, W. Kruczała, M. Kudła, H. Kudo, R. Kumagai, K. Kurogome, A. Kurosu, M. Kuse, A. Lacombe, E. Lefaillet, M. Magara, J. Malinowska, M. Malinowski, V. Maroselli, Y. Masui, K. Matsukawa, K. Matsuya, B. Matusik, M. Maulny, P. Mazur, C. Miyake, Y. Miyamoto, K. Miyata, K. Miyata, M. Miyazaki, M. Molęda, T. Morioka, E. Morita, K. Muto, H. Nadamoto, M. Nadzikiewicz, K. Nagashima, M. Nakade, C. Nakayama, H. Nakazawa, Y. Nihei, R. Nikul, S. Niwa, O. Niwa, M. Nogi, K. Nomura, D. Ogata, H. Ohguchi, J. Ohno, M. Okabe, M. Okada, Y. Okada, N. Omi, H. Onodera, K. Onodera, S. Ooki, K. Oonishi, H. Oonuma, H. Ooshima, H. Oouchi, M. Orsucci, M. Paoli, M. Penaud, C. Perdrisot, M. Petit, A. Piskowski, A. Płocharski, A. Polis, L. Polti, T. Potsepnia, D. Przybylski, M. Pytel, W. Quillet, A. Remy, C. Robert, M. Sadowski, M. Saito, D. Sakuma, K. Sano, Y. Sasaki, N. Sato, T. Schneider, C. Schneider, K. Schwartzman, E. Selivanov, M. Sezaki, K. Shiroishi, I. Shustava, A. Śniecińska, E. Stalchenko, A. Staroń, M. Stromboni, W. Studzińska, H. Sugisaki, T. Sukegawa, M. Sumida, Y. Suzuki, K. Suzuki, R. Suzuki, H. Suzuki, K. Suzuki, W. Świderski, M. Szudejko, M. Szymaszek, J. Tada, H. Taguchi, K. Takahashi, D. Tanaka, G. Tanaka, S. Tanaka, K. Tanino, K. Tazbir, N. Tcesnokova, N. Tgawa, N. Toda, H. Tsuchiya, H. Tsukamoto, T. Tsushima, K. Tsutsumi, H. Umemura, M. Uno, A. Usui, H. Utsumi, M. Vaucelle, Y. Wada, K. Watanabe, S. Watanabe, K. Watase, M. Witkowski, T. Yamaki, J. Yamamoto, T. Yamamoto, M. Yamashita, M. Yanai, K. Yasuda, Y. Yoshida, A. Yoshida, K. Yoshimura, M. Żmijewska, E. Zuclarelli
R. Khasanov, T. Schneider, H. Keller
Measurements of the magnetization under high hydrostatic pressure (up to 10.2 kbar) in YBa_2Cu_4O_8 were carried out. From the scaling analysis of the magnetization data the pressure induced shifts of the transition temperature T_c, the volume V and the anisotropy γhave been obtained. It was shown that the pressure induced relative shift of T_c mirrors essentially that of the anisotropy. This observation uncovers a novel generic property of anisotropic type II superconductors, that inexistent in the isotropic case.
E. Peik, B. Lipphardt, H. Schnatz, T. Schneider, Chr. Tamm, S. G. Karshenboim
We describe experiments with an optical frequency standard based on a laser cooled $^{171}$Yb$^+$ ion confined in a radiofrequency Paul trap. The electric-quadrupole transition from the $^2S_{1/2}(F=0)$ ground state to the $^2D_{3/2}(F=2)$ state at the wavelength of 436 nm is used as the reference transition. In order to compare two $^{171}$Yb$^+$ standards, separate frequency servo systems are employed to stabilize two probe laser frequencies to the reference transition line centers of two independently stored ions. The experimental results indicate a relative instability (Allan standard deviation) of the optical frequency difference between the two systems of $σ_y(1000 {\rm s})=5\cdot 10^{-16}$ only, so that shifts in the sub-hertz range can be resolved. Shifts of several hertz are observed if a stationary electric field gradient is superimposed on the radiofrequency trap field. The absolute optical transition frequency of Yb$^+$ at 688 THz was measured with a cesium atomic clock at two times separated by 2.8 years. A temporal variation of this frequency can be excluded within a $1σ$ relative uncertainty of $4.4\cdot 10^{-15}$ yr$^{-1}$. Combined with recently published values for the constancy of other transition frequencies this measurement provides a limit on the present variability of the fine structure constant $α$ at the level of $2.0\cdot 10^{-15}$ yr$^{-1}$.
T. Schneider, H. Keller
Anisotropy, thermal and quantum fluctuations and their dependence on dopant concentration appear to be present in all cuprate superconductors, interwoven with the microscopic mechanisms responsible for superconductivity. Here we review anisotropy, in-plane and c-axis penetration depths, isotope effect and conductivity measurements to reassess the universal behavior of cuprates as revealed by the doping dependence of these phenomena and of the transition temperature.
E. Peik, B. Lipphardt, H. Schnatz, T. Schneider, Chr. Tamm, S. G. Karshenboim
The comparison of different atomic transition frequencies over time can be used to determine the present value of the temporal derivative of the fine structure constant alpha in a model-independent way without assumptions on constancy or variability of other parameters. We have measured an optical transition frequency at 688 THz in ^{171}Yb+ with a cesium atomic clock at two times separated by 2.8 years and find a value for the fractional variation of the frequency ratio $f_{\rm Yb}/f_{\rm Cs}$ of $(-1.2\pm 4.4)\cdot 10^{-15}$ yr$^{-1}$, consistent with zero. Combined with recently published values for the constancy of other transition frequencies this measurement sets an upper limit on the present variability of alpha at the level of $2.0\cdot 10^{-15}$ yr$^{-1}$, corresponding so far to the most stringent limit from laboratory experiments.
T. Schneider, R. Khasanov, H. Keller
We analyze magnetic penetration depth data of the recently discovered superconducting pyrochlore oxide RbOs2O6. Our results strongly suggest that in RbOs2O6 charged critical fuctuations dominate the temperature dependence of the magnetic penetration depth near Tc. This is in contrast to the mean-field behavior observed in conventional superconductors and the uncharged critical behavior found in nearly optimally doped cuprate superconductors. However, this finding agrees with the theoretical predictions for charged criticality and the charged criticality observed in underdoped YBa2Cu3O6.59.
T. Schneider, R. Khasanov, K. Conder, E. Pomjakushina, R. Bruetsch, H. Keller
We report and analyze in-plane penetration depth measurements in YBa2Cu3O7-x taken close to the critical temperature Tc. In underdoped YBa2Cu3O6:59 we find consistent evidence for charged critical behavior. Noting that the effective dimensionless charge scales as 1/sqrt(Tc), this new critical behavior should be generically observable in suitably underdoped cuprates.
T. Schneider
We review and refine the finite size scaling analysis of specific heat and London penetration depths data of cuprate superconductors and compare it to the analysis of specific heat measurements near the superfluid transition of 4He confined to 1mum^3 cylindrical boxes. This system crosses from 3D to 0D behavior near the transition. This has a marked effect on the specific heat as seen by a pronounced rounding of the maximum and a shift to a temperature lower than the transition temperature of the bulk system. The region in between the 3D to 0D crossover uncovers the contributions from the surface and the edges of the cylindrical boxes. Our finite size scaling analysis of the specific heat and London penetration depth of high quality Y-123 and Bi-2212 single crystals uncover essentially the same crossover phenomena, including evidence for surface and edge contributions. These uncovers granular superconductivity in the samples considered here.
H. Keller, T. Schneider
Granularity, anisotropy, local lattice distortions and their dependence on dopant concentration appear to be present in all cuprate superconductors, interwoven with the microscopic mechanisms responsible for superconductivity. Here we review anisotropy and penetration depth measurements to reassess the evidence for granularity, as revealed by the notorious rounded phase transition, the evidence for the three dimensional nature of superconductivity, uncovered by the doping dependence of transition temperature and anisotropy, and to reassess the relevance of the electron-lattice coupling, emerging from the oxygen isotope effects.
T. Schneider, D. Di Castro
We report on a systematic finite size scaling analysis of in-plane penetration depth data taken on Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+δ}$ epitaxially-grown films and single crystals, and of in-plane and out of plane data taken on YBa$_{2}$Cu$_{3}$O$_{6.7}$ aligned powder. It is shown that the tails in temperature dependence of the penetration depths, appearing around the transition temperature, are fully consistent with a finite size effect. This uncovers the granular nature of these cuprates, consisting of superconducting homogeneous domains of nanoscale extent, embedded in a non-superconducting matrix.