English
Related papers

Related papers: Quasiparticle interference as a direct experimenta…

200 papers

We present angle resolved photoemission experiments and scanning tunneling spectroscopy results on the doped topological insulator Cu0.2Bi2Te3. Quasi-particle interference (QPI) measurements, based on high resolution conductance maps of the…

Mesoscale and Nanoscale Physics · Physics 2019-01-29 E. van Heumen , G. A. R. van Dalum , J. Kaas , N. de Jong , J. Oen , Y. K. Huang , A. K. Mitchell , L. Fritz , M. S. Golden

We study decoherence in superconducting qubits due to quasiparticle tunneling which is enhanced by two known deviations from the equilibrium BCS theory. The first process corresponds to tunneling of an already existing quasiparticle across…

Mesoscale and Nanoscale Physics · Physics 2012-04-20 Juha Leppäkangas , Michael Marthaler

A ferromagnetic insulator (FI) in contact with a superconductor (S) is known to induce a spin splitting of the BCS density of states at the FI/S interface. This spin splitting causes the Cooper pairs to reduce their singlet-state…

Superconductivity · Physics 2022-05-10 Alberto Hijano , Vitaly N. Golovach , F. Sebastián Bergeret

Recently reported quasiparticle interference imaging in underdoped Ca(Fe{1-x}Co{x})_2As{2} shows pronounced C{2} asymmetry that is interpreted as an indication of an electronic nematic phase with a unidirectional electron band, dispersive…

Superconductivity · Physics 2011-02-10 I. I. Mazin , Simon A. J. Kimber , Dimitri N. Argyriou

When the impurity mean free path is short, only spin-polarized Cooper pairs which are non-locally and antisymmetrically correlated in time may exist in a half-metallic ferromagnet. As a consequence, the half-metal acts as an odd-frequency…

Superconductivity · Physics 2020-10-30 Eirik Holm Fyhn , Jacob Linder

We investigate subgap quasiparticles of a single level quantum dot coupled to the superconducting and normal leads, whose energy level is periodically driven by external potential. Using the Floquet formalism we determine the quasienergies…

Mesoscale and Nanoscale Physics · Physics 2019-08-14 B. Baran , T. Domański

Quantum nonlinear interferometers (QNIs) can measure the infrared physical quantities of a sample by detecting visible photons. A QNI with Michelson geometry based on the spontaneous parametric down-conversion in a second-order nonlinear…

Tunneling of fractionally charged quasi-particles (QPs) through a barrier is considered in the context of a multiply connected geometry. In this geometry global constraints do not prohibit such a tunneling process. The tunneling amplitude…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Elad Shopen , Yuval Gefen , Yigal Meir

We demonstrate optical interferometry beyond the limits imposed by the photon wavelength using 'triggered' entangled photon pairs from a semiconductor quantum dot. Interference fringes of the entangled biphoton state reveals a periodicity…

Quantum Physics · Physics 2008-03-28 R. M. Stevenson , A. J. Hudson , R. J. Young , P. Atkinson , K. Cooper , D. A. Ritchie , A. J. Shields

We propose the ``pair-breaking scattering interference" as a general source of coherence peak modulations in superconductors. Assuming this mechanism, we present a simple physical picture for the coherence peak modulations in overdoped…

Superconductivity · Physics 2024-12-16 Zhi-Qiang Gao , Yu-Ping Lin , Dung-Hai Lee

The pairing mechanism in the iron pnictides remains unresolved yet. One of the central issues is the structure of the superconducting order parameter which classifies the community into two different and highly disputed camps. On one hand…

Superconductivity · Physics 2014-04-18 Huan Yang , Zhenyu Wang , Delong Fang , Qiang Deng , Qiang-Hua Wang , Yuan-Yuan Xiang , Yang Yang , Hai-Hu Wen

The proper functioning of some micro-fabricated novel quantum devices, such as superconducting resonators and qubits, is severely affected by the presence of parasitic structural material defects known as tunneling two-level-systems (TLS).…

Superconductivity · Physics 2022-02-01 Octavio de los Santos-Sánchez , Ricardo Román-Ancheyta

We present a general theory of quasiparticle number fluctuations in superconductors. The theory uses the master equation formalism. First, we develop the theory for a single occupation variable. Although this simple system is insufficient…

Superconductivity · Physics 2010-03-09 C. M. Wilson , D. E. Prober

By using Fourier-transform scanning tunneling spectroscopy we measure the interference patterns produced by the impurity scattering of confined Dirac quasiparticles in epitaxial graphene nanoflakes. Upon comparison of the experimental…

Mesoscale and Nanoscale Physics · Physics 2017-02-28 Julia Tesch , Philipp Leicht , Felix Blumenschein , Luca Gragnaniello , Anders Bergvall , Tomas Löfwander , Mikhail Fonin

The ideal superconductor provides a pristine environment for the delicate states of a quantum computer: because there is an energy gap to excitations, there are no spurious modes with which the qubits can interact, causing irreversible…

Following nearly a century of research, it remains a puzzle that the low-lying excitations of metals are remarkably well explained by effective single-particle theories of non-interacting bands. The abundance of interactions in real…

Strongly Correlated Electrons · Physics 2023-09-21 Nico Huber , Valentin Leeb , Andreas Bauer , Georg Benka , Johannes Knolle , Christian Pfleiderer , Marc A. Wilde

Bicoherence is a way to measure the phase coupling of triplets of Fourier frequencies. We use this method to analyze quasi-periodic oscillations (QPOs) in the black hole X-ray binary MAXI J1535$-$571 during its 2017 September-October…

High Energy Astrophysical Phenomena · Physics 2024-03-21 Ziyuan Zhu , Xiao Chen , Wei Wang

The local density of states power spectrum of optimally doped Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ (BSCCO) has been interpreted in terms of quasiparticle interference peaks corresponding to an "octet'' of scattering wave vectors connecting…

Superconductivity · Physics 2007-05-23 Tamara S. Nunner , Wei Chen , Brian M. Andersen , Ashot Melikyan , P. J. Hirschfeld

The evolution of the quantum wave packet describing an atom trapped in the surface-tip junction of the scanning tunneling microscope is investigated by using the time-dependent Schroedinger equation, and by a quasi-classical Hamiltonian…

Quantum Physics · Physics 2008-02-21 M. Grigorescu

Superconductivity is characterized by a nonvanishing superconducting pair amplitude. It has a definite symmetry in spin, momentum and frequency (time). While the spin and momentum symmetry have been probed experimentally for different…

Mesoscale and Nanoscale Physics · Physics 2018-10-31 Sun-Yong Hwang , Pablo Burset , Björn Sothmann