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The topological order of a quantum Hall state is mirrored by the gapless edge modes owing to bulk-edge correspondence. The state at the filling of n = 5/2, predicted to host non-abelian anyons, supports a variety of edge modes (integer, fractional, neutral). To ensure thermal equilibration between the edge modes and thus accurately determine the stateÕs nature, it is advantageous to isolate the fractional channel (1/2 and neutral modes). In this study, we gapped out the integer modes by interfacing the n = 5/2 state with integer states n = 2 and n = 3 and measured the thermal conductance of the isolated-interface channel. Our measured half-quantized thermal conductance confirms the non-abelian nature of the n = 5/2 state and its particle-hole Pfaffian topological order. Such an isolated channel may be more amenable to braiding experiments. [ABSTRACT FROM AUTHOR]

As an emergent electronic material and model system for condensed-matter physics, graphene and its electrical transport properties have become a subject of intense focus. By performing low-temperature transport spectroscopy on single-layer and bilayer graphene, we observe ballistic propagation and quantum interference of multiply reflected waves of charges from normal electrodes and multiple Andreev reflections from superconducting electrodes, thereby realizing quantum billiards in which scattering only occurs at the boundaries. In contrast to the conductivity of conventional two-dimensional materials, graphene's conductivity at the Dirac point is geometry-dependent because of conduction via evanescent modes, approaching the theoretical value 4e2/πh (where e is the electron charge and h is Planck's constant) only for short and wide devices. These distinctive transport properties have important implications for understanding chaotic quantum systems and implementing nanoelectronic devices, such as ballistic transistors. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor focuses on materials research of graphene by Lee and others measuring the response of multiple layers of graphene to the projection of microbullets using miniaturized ballistics tests and confirmed the exceptional stiffness and strength of graphene.

Reports on the failure of the old-standard fingerprinting on the standards of the Supreme Court in the United States. Limitation on the claims of fingerprint examinations in the courtroom; Challenges on the scientific credibility of ballistics and other forensic techniques; Qualification of technique and technology in the court.