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We introduce a method to fabricate high-performance field-effect transistors on the surface of freestanding organic single crystals. The transistors are constructed by laminating a monolithic elastomeric transistor stamp against the surface of a crystal. This method, which eliminates exposure of the fragile organic surface to the hazards of conventional processing, enables fabrication of rubrene transistors with charge carrier mobilities as high as$\\sim 15 cm^2/V\\cdot s$and subthreshold slopes as low as$2 nF\\cdot V/decade\\cdot cm^2$. Multiple relamination of the transistor stamp against the same crystal does not affect the transistor characteristics; we exploit this reversibility to reveal anisotropic charge transport at the basal plane of rubrene.

The submillimetre or terahertz region of the electromagnetic spectrum contains approximately half of the total luminosity of the Universe and 98% of all the photons emitted since the Big Bang 1 . This radiation is strongly absorbed in the Earth's atmosphere, so space-based terahertz telescopes are crucial for exploring the evolution of the Universe 2 , 3 . Thermal emission from the primary mirrors in these telescopes can be reduced below the level of the cosmic background by active cooling, which expands the range of faint objects that can be observed. However, it will also be necessary to develop bolometers—devices for measuring the energy of electromagnetic radiation—with sensitivities that are at least two orders of magnitude better than the present state of the art. To achieve this sensitivity without sacrificing operating speed, two conditions are required. First, the bolometer should be exceptionally well thermally isolated from the environment; second, its heat capacity should be sufficiently small. Here we demonstrate that these goals can be achieved by building a superconducting hot-electron nanobolometer. Its design eliminates the energy exchange between hot electrons and the leads by blocking electron outdiffusion and photon emission. The thermal conductance between hot electrons and the thermal bath, controlled by electron–phonon interactions, becomes very small at low temperatures (∼1 × 10 −16  W K −1 at 40 mK). These devices, with a heat capacity of ∼1 × 10 −19  J K −1 , are sufficiently sensitive to detect single terahertz photons in submillimetre astronomy and other applications based on quantum calorimetry and photon counting. By carefully controlling the heat capacity and other thermal properties of a superconducting hot-electron nanobolometer, researchers have built a device that is sufficiently sensitive to detect single terahertz photons, making it suitable for use in a future space-based terahertz telescope.

For successful realization of a quantum computer, its building blocks—the individual qubits—should be simultaneously scalable and sufficiently protected from environmental noise. Recently, a novel approach to the protection of superconducting qubits has been proposed. The idea is to prevent errors at the hardware level, by building a fault-free logical qubit from ‘faulty’ physical qubits with properly engineered interactions between them. The decoupling of such a topologically protected logical qubit from local noises is expected to grow exponentially with the number of physical qubits. Here, we report on proof-of-concept experiments with a prototype device that consists of twelve physical qubits made of nanoscale Josephson junctions. We observed that owing to properly tuned quantum fluctuations, this qubit is protected against magnetic flux variations well beyond linear order, in agreement with theoretical predictions. These results suggest that topologically protected superconducting qubits are feasible. An array of superconducting nanocircuits has been designed that provides built-in protection from environmental noises. Such ‘topologically protected’ qubits could lead the way to a scalable architecture for practical quantum computation.

Josephson junctions (JJs) with Josephson energy EJ≲1 K are widely employed as non-linear elements in superconducting circuits for quantum computing operating at milli-Kelvin temperatures. In the qubits with small charging energy EC ( EJ/EC≫1 ), such as the transmon, the incoherent phase slips (IPS) might become the dominant source of dissipation with decreasing EJ. In this work, a systematic study of the IPS in low-EJ JJs at milli-Kelvin temperatures is reported. Strong suppression of the critical (switching) current and a very rapid growth of the zero-bias resistance due to the IPS are observed with decreasing EJ below 1 K. With further improvement of coherence of superconducting qubits, the observed IPS-induced dissipation might limit the performance of qubits based on low-EJ junctions. These results point the way to future improvements of such qubits.

Experiments with superconductor-graphene hybrids, a novel platform to study quantum phase transitions, suggest that in the proximity of the critical point between superconducting and insulating phases, inhomogeneity emerges at large scales even in apparently uniform disordered systems.

Experiments with superconductor–graphene hybrids, a novel platform to study quantum phase transitions, suggest that in the proximity of the critical point between superconducting and insulating phases, inhomogeneity emerges at large scales even in apparently uniform disordered systems.

We have designed superinductors made of strongly disordered superconductors for implementation in \"hybrid\" superconducting quantum circuits. The superinductors have been fabricated as meandered nanowires made of granular Aluminum films. Optimization of the device geometry enabled realization of superinductors with the inductance \\(\\sim 1 {\\mu}H\\) and the self-resonance frequency over 3 GHz. These compact superinductors are attractive for a wide range of applications, from superconducting circuits for quantum computing to microwave elements of cryogenic parametric amplifiers and kinetic-inductance photon detectors.

Josephson junctions (JJs) with Josephson energy \\(E_J \\lesssim 1K\\) are widely employed as non-linear elements in superconducting circuits for quantum computing, operating at milli-Kelvin temperatures. Here we experimentally study incoherent phase slips (IPS) in low-\\(E_J\\) Aluminum-based JJs at \\(T<0.2K\\), where the IPS become the dominant source of dissipation. We observed strong suppression of the critical (switching) current and a very rapid growth of the zero-bias resistance with decreasing Josephson energy below \\(E_J \\sim 1K\\). This behavior is attributed to the IPSs whose rate exponentially increases with decreasing the ratio \\(E_J/T\\). Our observations are in line with other data reported in literature. With further improvement of coherence of superconducting qubits, the observed dissipation from IPS might limit the performance of qubits based on low-\\(E_J\\) junctions.