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Related papers: Weak measurement of quantum dot spin qubits

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We show that the correlations in stochastic outputs of time-distributed weak measurements can be used to study the dynamics of an individual quantum object, with a proof-of-principle setup based on small Faraday rotation caused by a single…

Mesoscale and Nanoscale Physics · Physics 2010-01-20 R. -B. Liu , Shu-Hong Fung , Hok-Kin Fung , A. N. Korotkov , L. J. Sham

Quantum measurements not only extract information from a system but also alter its state. Although the outcome of the measurement is probabilistic, the backaction imparted on the measured system is accurately described by quantum theory.…

Quantum Physics · Physics 2014-04-21 M. S. Blok , C. Bonato , M. L. Markham , D. J. Twitchen , V. V. Dobrovitski , R. Hanson

The standard method of "measuring" quantum wavefunction is the technique of {\it indirect} quantum state tomography. Owing to conceptual novelty and possible advantages, an alternative {\it direct} scheme was proposed and demonstrated…

Quantum Physics · Physics 2023-09-26 Lupei Qin , Luting Xu , Wei Feng , Xin-Qi Li

Quantum technology has been rapidly growing due to its potential revolutionary applications. In particular, superconducting qubits provide a strong light-matter interaction as required for quantum computation and in principle can be scaled…

Quantum Physics · Physics 2019-04-23 Mahdi Naghiloo

The understanding of weak measurements and interaction-free measurements has greatly expanded the conceptual and experimental toolbox to explore the quantum world. Here we demonstrate single-shot variable-strength weak measurements of the…

In this review we discuss a recent proposal to perform partial Bell-state (parity) measurements on two-electron spin states for electrons confined to quantum dots. The realization of this proposal would allow for a physical implementation…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 W. A. Coish , Vitaly N. Golovach , J. Carlos Egues , Daniel Loss

Quantum measurements are described as instantaneous projections in textbooks. They can be stretched out in time using weak measurements, whereby one can observe the evolution of a quantum state as it heads towards one of the eigenstates of…

Quantum Physics · Physics 2018-04-11 Parveen Kumar , Suman Kundu , Madhavi Chand , R. Vijayaraghavan , Apoorva Patel

Precisely knowing an interaction Hamiltonian is crucial to realize quantum information tasks, especially to experimentally demonstrate a quantum computer and a quantum memory. We propose a scheme to experimentally evaluate the spin-spin…

Quantum Physics · Physics 2011-11-10 Yutaka Shikano , Shu Tanaka

Several topics on the implementation of spin qubits in quantum dots are reviewed. We first provide an introduction to the standard model of quantum computing and the basic criteria for its realization. Other alternative formulations such as…

Mesoscale and Nanoscale Physics · Physics 2010-07-20 Robert Andrzej Żak , Beat Röthlisberger , Stefano Chesi , Daniel Loss

IIt is shown that a weak measurement of a quantum system produces a new state of the quantum system which depends on the prior state, as well as the (uncontrollable) measured position of the pointer variable of the weak measurement…

Quantum Physics · Physics 2013-05-29 D. J. Miller

Entangled states in high dimensional systems are of great interest due to the extended possibilities they provide in quantum information processing. Recently, Sun et al. [Phys. Rev. A 82, 052323 (2010)] and Kim et al. [Nat. Phys. 8, 117…

Quantum Physics · Physics 2017-07-03 Xing Xiao , Yan-Ling Li

Weak quantum measurements enable real-time tracking and control of dynamical quantum systems, producing quantum trajectories -- evolutions of the quantum state of the system conditioned on measurement outcomes. For classical systems, the…

We review progress on the spintronics proposal for quantum computing where the quantum bits (qubits) are implemented with electron spins. We calculate the exchange interaction of coupled quantum dots and present experiments, where the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Hans-Andreas Engel , L. P. Kouwenhoven , Daniel Loss , C. M. Marcus

Measurement plays a quintessential role in the control of quantum systems. Beyond initialization and readout which pertain to projective measurements, weak measurements in particular, through their back-action on the system, may enable…

Quantum Physics · Physics 2022-06-07 Yunzhao Wang , Kyrylo Snizhko , Alessandro Romito , Yuval Gefen , Kater Murch

Understanding the interplay between a quantum system and its environment lies at the heart of quantum science and its applications. To-date most efforts have focused on circumventing decoherence induced by the environment by either…

Quantum discord is a measure based on local projective measurements which captures quantum correlations that may not be fully captured by entanglement. A change in the measurement process, achieved by replacing rank-one projectors with a…

Quantum Physics · Physics 2020-08-17 Akanksha Gautam , Varad R. Pande , Amandeep Singh , Kavita Dorai , Arvind

Traditional uncertainty relations dictate a minimal amount of noise in incompatible projective quantum measurements. However, not all measurements are projective. Weak measurements are minimally invasive methods for obtaining partial state…

Quantum Physics · Physics 2021-03-15 Jonathan T. Monroe , Nicole Yunger Halpern , Taeho Lee , Kater W. Murch

Acquiring information about an unknown qubit in a superposition of two states is essential in any computation process. Quantum measurement, or sharp measurement, is usually used to read the information contents of that unknown qubit system.…

Quantum Physics · Physics 2017-04-26 Ahmed Younes

The effects of different forms of weak measurements on the nature of the measurement induced phase transition are theoretically studied in hybrid random quantum circuits of qubits. We use a combination of entanglement measures, ancilla…

Quantum Physics · Physics 2024-12-10 Kemal Aziz , Ahana Chakraborty , J. H. Pixley

Continuous weak measurement allows localizing open quantum systems in state space, and tracing out their quantum trajectory as they evolve in time. Efficient quantum measurement schemes have previously enabled recording quantum trajectories…

Quantum Physics · Physics 2019-10-15 Massimiliano Rossi , David Mason , Junxin Chen , Albert Schliesser