English
Related papers

Related papers: Logical XOR gate response in a quantum interferome…

200 papers

We study electron transport through multiply-connected mesoscopic geometries containing interacting quantum dots. Our formulation covers both equilibrium and non-equilibrium physics. We discuss the relation of coherent transport channels…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Jürgen König , Yuval Gefen

Here we propose four-terminal molecular devices as functional logic gates (AND, NOR and XOR, respectively). Such devices are composed of single organic molecule connected to gold electrodes and located in between gate terminals.…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Kamil Walczak

Electron transport properties of a biphenyl molecule are studied based on the Green's function formalism. The molecule is sandwiched between two metallic electrodes, where each benzene ring is threaded by a magnetic flux $\phi$. The results…

Mesoscale and Nanoscale Physics · Physics 2009-09-15 Santanu K. Maiti

Quantum Logic Processors can be implemented with Mach Zehnder Interferometer(MZI) configurations for the Quantum logic operations and gates. In this paper, its implementation for both optical and electronic system has been presented. The…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Angik Sarkar , T. K. Bhattacharyya , Ajay Patwardhan

We suggest coherent switching of canted antiferromagnetic (AFM) spins using spin-orbit torque (SOT) in small magnet. The magnetic system of orthoferrite features biaxial easy anisotropy and the Dzyaloshinskii Moriya interaction, which is…

Materials Science · Physics 2021-08-18 T. H. Kim , S. Hwang , S. Y. Hamh , S. H. Yoon , S. H. Han , B. K. Cho

We design spin filters for particles with potentially arbitrary spin S (= 1/2, 1, 3/2,....) using a one-dimensional periodic chain of magnetic atoms as a quantum device. Describing the system within a tight-binding formalism we present an…

Mesoscale and Nanoscale Physics · Physics 2016-08-02 Biplab Pal , Rudolf A. Römer , Arunava Chakrabarti

We show that a strongly correlated quantum dot embedded in an Aharonov-Bohm interferometer can be used to filter both charge and spin at zero voltage bias. The magnitude with which the Aharonov-Bohm arm is coupled to the system controls the…

Strongly Correlated Electrons · Physics 2009-11-13 R. J. Heary , J. E. Han , Lingyin Zhu

We address the question of how to model electron transport through closed Aharonov-Bohm interferometers which contain quantum dots. By explicitly studying interferometers with one and two quantum dots, we establish the connection between a…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Björn Kubala , Jürgen König

In a quantum ring connected with two external leads the spin properties of an incoming electron are modified by the spin-orbit interaction resulting in a transformation of the qubit state carried by the spin. The ring acts as a one qubit…

Quantum Physics · Physics 2009-11-10 Peter Foldi , Balazs Molnar , Mihaly G. Benedict , F. M. Peeters

Although the conductance of a closed Aharonov-Bohm interferometer, with a quantum dot on one branch, obeys the Onsager symmetry under magnetic field reversal, it needs not be a periodic function of this field: the conductance maxima move…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Amnon Aharony , Ora Entin-Wohlman , Tomohiro Otsuka , Shingo Katsumoto , Hisashi Aikawa , Kensuke Kobayashi

The microreversibility principle implies that the conductance of a two-terminal Aharonov-Bohm interferometer is an even function of the applied magnetic flux. Away from linear response, however, this symmetry is not fulfilled and the…

Mesoscale and Nanoscale Physics · Physics 2010-04-29 Jong Soo Lim , David Sanchez , Rosa Lopez

Favored schemes for trapped-ion quantum logic gates use bichromatic laser fields to couple internal qubit states with external motion through a "spin-dependent force." We introduce a new degree of freedom in this coupling that reduces its…

Quantum Physics · Physics 2009-11-10 P. C. Haljan , K. -A. Brickman , L. Deslauriers , P. J. Lee , C. Monroe

Current-driven switching of nonvolatile spintronic materials and devices based on spin-orbit torques offer fast data processing speed, low power consumption, and unlimited endurance for future information processing applications. Analogous…

Mesoscale and Nanoscale Physics · Physics 2020-07-23 Nan Zhang , Yi Cao , Yucai Li , Andrew W. Rushforth , Yang Ji , Houzhi Zheng , Kaiyou Wang

We theoretically investigate electron transport through an Aharonov-Bohm interferometer containing laterally coupled double quantum dots. We introduce the indirect coupling parameter $\alpha$, which characterizes the strength of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Toshihiro Kubo , Yasuhiro Tokura , Tsuyoshi Hatano , Seigo Tarucha

We investigate two schemes for pumping spin adiabatically from a ferromagnet through an interacting quantum dot into a normal lead, which exploit the possibility to vary in time the ferromagnet's magnetization, either its amplitude or its…

Mesoscale and Nanoscale Physics · Physics 2013-05-17 Nina Winkler , Michele Governale , Jürgen König

We present an electron interferometer defined purely by electrostatic gating in encapsulated bilayer graphene. This minimizes possible sample degradation introduced by conventional etching methods when preparing quantum devices. The device…

We study the spin transport in the quantum Heisenberg spin chain subject to boundary magnetic fields and driven out of equilibrium by Lindblad dissipators. An exact solution is given in terms of matrix product states, which allows us to…

Quantum Physics · Physics 2015-06-30 Gabriel T. Landi , Dragi Karevski

A brief review is given of the physical implementation of quantum computation within spin systems or other two-state quantum systems. The importance of the controlled-NOT or quantum XOR gate as the fundamental primitive operation of quantum…

Mesoscale and Nanoscale Physics · Physics 2009-10-28 David P. DiVincenzo

We analyze the heat current traversing a quantum dot sandwiched between a ferromagnetic and a superconducting electrode. The heat flow generated in response to a voltage bias presents rectification as a function of the gate potential…

Mesoscale and Nanoscale Physics · Physics 2018-04-24 Sun-Yong Hwang , David Sanchez

We propose a hybrid quantum system, where an $LC$ resonator inductively interacts with a flux qubit and is capacitively coupled to a Rydberg atom. Varying the external magnetic flux bias controls the flux-qubit flipping and the flux…

Atomic Physics · Physics 2017-08-24 Deshui Yu , Leong Chuan Kwek , Luigi Amico , Rainer Dumke