Coupled chemical-mechanical defibrillation and self-assembly processes have been successfully established for creating super-fine (125-497 nm wide) highly crystalline (63.2-71.5% CrI) cellulose Iβ fibrous materials from rice straw cellulose. Under the optimized TEMPO mediated oxidation with 5 mmol g ^-1 NaClO/cellulose followed by 30 min mechanical blending, highly uniform (2.09 nm wide, 1.52 nm thick, up to 1 μm long) cellulose nanofibrils (CNFs) were efficiently derived at an impressive 96.8% yield and contained 1.29 mmol surface carboxyls per g of cellulose or 0.21 COOH/anhydroglucose (AG), representing 70.9% surface C6 primary hydroxyl to carboxyl conversion. Rapid freezing of aqueous CNF suspensions in liquid nitrogen and freeze-drying induced self-assembly of these nanofibrils into white fluffy fibrous materials via ice-crystal templating. The self-assembled fiber morphologies showed a strong dependence on CNF morphologies and extent of surface carboxylation. CNFs with 37.3% conversion of surface carboxyls assembled into 125 nm wide fibers, whereas wider fibers (327 nm and 497 nm) were assembled from the smaller CNFs and more carboxylated (51.5% and 70.9%, respectively) surfaces. This robust defibrillation-assembly approach offers new versatile and scalable alternatives to fabricate super-fine cellulose fibers with a highly crystalline cellulose Iβ structure from the by-product of the largest cereal crop in the world. © The Royal Society of Chemistry 2013.

The Josephson Ic between a Ta-wire probe and an induced, surface, singlet, superconducting state in UBe13 decreases with decreasing temperature below the bulk UBe13 Tc, in contrast to the increase seen in comparison Mo samples. This shows that the bulk UBe13 superconductivity suppresses the induced singlet superconductivity. Such suppression is evidence of a triplet super-conducting state in UBe13. Evidence is presented for phase slip between weakly coupled singlet and triplet order parameters. © 1986 The American Physical Society.

Anomalous proximity-induced s-wave superconductivity has been observed via the ac Josephson effect and the magnetic field and temperature dependences of the Josephson current in Nb/CeCu2Si2, Nb/LaBe13, and Nb/UBe13 junctions. The origin of the proximity-induced Josephson effect and its utility in discovering the pairing type in heavy-fermion metals are discussed. © 1985 The American Physical Society.

The proximity-Josephson effect (PJE) is a powerful general method of determining the symmetry of the pair wave function in exotic superconductors. The method is simple and relatively insensitive to the surface condition of the sample. A superconducting probe (S) of known pairing symmetry (typically Nb or Ta) is brought into contact with the sample (N). Observations and arguments based on the de Gennes boundary condition at the NS interface both indicate formation of a local, proximity-induced superconducting region of depth ξ in the sample (N) under the probe. The induced pairs have the same symmetry as those of S. The expected pair-phase dependence of the coupling energy between the pairs in N and S leads to a Josephson current Ic(T), which may be observed up to a junction critical temperature T* which is typically ∼0.8 of the Tc of S. When the measurement temperature falls below the bulk Tc of N (the exotic superconductor), a pair wave function of possibly different symmetry forms in the bulk of N and overlaps the induced pair wave function near the probe. Weak interactions between the induced and bulk pairs occur. In the case of UBe13 contacted with a Ta tip, the interaction weakly suppresses the induced pairs [which determine Ic(T)] leading to a reduction of the Josephson current at T

We experimentally demonstrate that highly structured distributions of work emerge during even the simple task of erasing a single bit. These are signatures of a refined suite of time-reversal symmetries in distinct functional classes of microscopic trajectories. As a consequence, we introduce a broad family of conditional fluctuation theorems that the component work distributions must satisfy. Since they identify entropy production, the component work distributions encode the frequency of various mechanisms of both success and failure during computing, as well giving improved estimates of the total irreversibly dissipated heat. This new diagnostic tool provides strong evidence that thermodynamic computing at the nanoscale can be constructively harnessed. We experimentally verify this functional decomposition and the new class of fluctuation theorems by measuring transitions between flux states in a superconducting circuit.

We implement a thermal-fluctuation-driven logical bit reset on a superconducting flux logic cell. We show that the logical state of the system can be continuously monitored with only a small perturbation to the thermally activated dynamics at 500 mK. We use the trajectory information to derive a single-shot estimate of the work performed on the system per logical cycle. We acquire a sample of 105 erasure trajectories per protocol and show that the work histograms agree with both microscopic theory and global fluctuation theorems. The results demonstrate how to design and diagnose complex, high-speed, and thermodynamically efficient computing using superconducting technology.

We experimentally demonstrate that highly structured distributions of work emerge during even the simple task of erasing a single bit. These are signatures of a refined suite of time-reversal symmetries in distinct functional classes of microscopic trajectories. As a consequence, we introduce a broad family of conditional fluctuation theorems that the component work distributions must satisfy. Since they identify entropy production, the component work distributions encode both the frequency of various mechanisms of success and failure during computing, as well giving improved estimates of the total irreversibly-dissipated heat. This new diagnostic tool provides strong evidence that thermodynamic computing at the nanoscale can be constructively harnessed. We experimentally verify this functional decomposition and the new class of fluctuation theorems by measuring transitions between flux states in a superconducting circuit.