English
Related papers

Related papers: A ballistic two-dimensional-electron-gas Andreev i…

200 papers

The subtle interplay between quantum statistics and interactions is at the origin of many intriguing quantum phenomena connected to superfluidity and quantum magnetism. The controlled setting of ultracold quantum gases is well suited to…

Using an ultra-low temperature, high magnetic field scanning probe microscope, we have measured electric potentials of a deeply buried two dimensional electron gas (2DEG). Relying on the capacitive coupling between the 2DEG and a resonant…

Mesoscale and Nanoscale Physics · Physics 2010-11-25 J. A. Hedberg , A. Lal , Y. Miyahara , P. Grütter , G. Gervais , M. Hilke , L. Pfeiffer , K. W. West

We have used a field-penetration method to measure thermodynamic compressibility of a moderately interacting two-dimensional electron system ($r_{s}$ $\approx$ 0.5-3) in a three terminal GaAs/AlGaAs device, fabricated with an epitaxial…

Strongly Correlated Electrons · Physics 2009-09-29 S. C. Dultz , B. Alavi , H. W. Jiang

We have measured weak antilocalization effects, universal conductance fluctuations, and Aharonov-Bohm oscillations in the two-dimensional electron gas formed in InGaAs/AlInAs heterostructures. This system possesses strong spin-orbit…

Mesoscale and Nanoscale Physics · Physics 2017-04-05 L. H. Tzarfati , A. Aharony , O. Entin-Wohlman , M. Karpovski , V. Shelukhin , V. Umansky , A. Palevski

Quantized conductance plateaus, a celebrated hallmark of Majorana bound states (MBSs) predicted a decade ago, have recently been observed with small deviations in iron-based superconductors and hybrid nanowires. Here, we demonstrate that…

Mesoscale and Nanoscale Physics · Physics 2023-09-18 Zhan Cao , Gu Zhang , Hao Zhang , Ying-Xin Liang , Wan-Xiu He , Ke He , Dong E. Liu

We calculate the spectrum of the Andreev boundary modes in a two-dimensional superconductor formed at an interface between two different non-superconducting materials, e.g. insulating oxides. Inversion symmetry is absent in this system, and…

Superconductivity · Physics 2016-10-05 K. V. Samokhin , S. P. Mukherjee

We report on transport characteristics of field effect two-dimensional electron gases (2DEG) in 24 nm wide indium arsenide surface quantum wells. High quality single-subband magnetotransport with clear quantized integer quantum Hall…

We describe magnetic field sensor based on spin wave interferometer. Its sensing element consists of a magnetic cross junction with four micro-antennas fabricated at the edges. Two of these antennas are used for spin wave excitation and two…

Other Condensed Matter · Physics 2016-11-28 M. Balynsky , D. Gutierrez , H. Chiang , A. Kozhevnikov , Y. Filimonov , A. A. Balandin , A. Khitun

Andreev reflection is a smart tool to investigate the spin polarisation P of the current through point contacts between a superconductor and a ferromagnet. We compare different models to extract P from experimental data and investigate the…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 S. Bouvron , M. Stokmaier , M. Marz , G. Goll

Andreev reflection-where an electron in a normal metal backscatters off a superconductor into a hole-forms the basis of low energy transport through superconducting junctions. Andreev reflection in confined regions gives rise to discrete…

Atom interferometric inertial sensors offer exceptional sensitivity but are fundamentally constrained by the periodic phase response of matter-wave interference, which imposes an intrinsic half-fringe dynamic-range limit and prevents…

We report on the low frequency noise in the ballistic point-contacts between a silver tip and a niobium foil. The ballistic nature of the point-contacts is confirmed by Andreev reflection spectroscopy at low bias voltage with the Nb foil…

Superconductivity · Physics 2014-10-15 Jian Wei , Goutam Sheet , Venkat Chandrasekhar

Point-contact Andreev reflection spectroscopy at low temperatures and high magnetic fields has been performed on a noncentrosymmetric La$_3$Se$_4$ superconductor with a critical temperature $T_c$ = 8 K. Two superconducting energy gaps…

New method to probe quantum dynamics of the order parameter phase of a small superconductive island is proposed. The idea is to measure Andreev subgap conductance between the island and a dirty normal-metal wire connected with the island by…

Condensed Matter · Physics 2007-05-23 M. V. Feigel'man , V. B. Geshkenbein , L. B. Ioffe , G. Blatter

Semiconductor nanowires coupled to a superconductor provide a powerful testbed for quantum device physics such as Majorana zero modes and gate-tunable hybrid qubits. The performance of these quantum devices heavily relies on the quality of…

Experimental support is found for the multiband model of the superconductivity in the recently discovered system MgB2 with the transition temperature Tc = 39 K. By means of Andreev reflection evidence is obtained for two distinct…

Superconductivity · Physics 2009-02-12 P. Szabo , P. Samuely , J. Kacmarcik , Th. Klein , J. Marcus , D. Fruchart , S. Miraglia , C. Marcenat , A. G. M. Jansen

We report new measurements on sup-gap energy structure originating from multiple Andreev reflections in mesoscopic SNS junctions. The junctions were fabricated in a planar geometry with high transparency superconducting contacts of Al…

We discuss very low temperature experiments on superconducting micro-coolers made of a double Normal metal - Insulator - Superconductor junction. We investigate with a high resolution the differential conductance of the micro-cooler as well…

Superconductivity · Physics 2009-11-13 Sukumar Rajauria , Philippe Gandit , F. W. J. Hekking , Bernard Pannetier , Hervé Courtois

Graphene is a material with remarkable electronic properties and exceptional thermal transport properties near room temperature, which have been well examined and understood. However at very low temperatures the thermodynamic and thermal…

Mesoscale and Nanoscale Physics · Physics 2012-08-02 Kin Chung Fong , Keith Schwab

We have investigated metallic break junctions of the heavy-fermion compound UPd2Al3 at low temperatures between 0.1K and 9K and in magnetic fields up to 8T. Both the current-voltage I(V) characteristics and the dV/dI (V) spectra clearly…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Yu. G. Naidyuk , K. Gloos , I. K. Yanson , N. K. Sato