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We study the two-electron eigenspectrum of a carbon-nanotube double quantum dot with spin-orbit coupling. Exact calculation are combined with a simple model to provide an intuitive and accurate description of single-particle and interaction…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 J. von Stecher , B. Wunsch , M. Lukin , E. Demler , A. M. Rey

A solid state spin is an attractive system with which to realize an ultra-sensitive magnetic field sensor. A spin superposition state will acquire a phase induced by the target field, and we can estimate the field strength from this phase.…

Quantum Physics · Physics 2017-04-05 Yuichiro Matsuzaki , Simon Benjamin

If unitary evolution of a quantum system is interrupted by a sequence of measurements we call the dynamics as quantum Zeno dynamics. We show that under quantum Zeno dynamics not only the transition probability (leading to quantum Zeno…

Quantum Physics · Physics 2007-05-23 Arun Kumar Pati , Suresh V. Lawande

Interaction of solid state qubits with environmental degrees of freedom strongly affects the qubit dynamics, and leads to decoherence. In quantum information processing with solid state qubits, decoherence significantly limits the…

Mesoscale and Nanoscale Physics · Physics 2010-02-26 Luca Chirolli , Guido Burkard

Spin-dependent transport measurements through a double quantum dot are a valuable tool for detecting both the coherent evolution of the spin state of a single electron as well as the hybridization of two-electron spin states. In this paper,…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 F. H. L. Koppens , C. Buizert , I. T. Vink , K. C. Nowack , T. Meunier , L. P. Kouwenhoven , L. M. K. Vandersypen

We investigate the effect of nuclear spins on the phase shift and polarisation rotation of photons scattered off a quantum dot-cavity system. We show that as the phase shift depends strongly on the resonance energy of an electronic…

Quantum Physics · Physics 2019-06-05 Thomas Nutz , Petros Androvitsaneas , Andrew Young , Ruth Oulton , Dara P. S. McCutcheon

We present a method of obtaining information about spin lifetimes in quantum dots from measurements of electrical transport. The dot is under resonant microwave irradiation and at temperatures comparable to or larger than the Zeeman energy.…

Mesoscale and Nanoscale Physics · Physics 2009-01-12 J. Wabnig , B. W. Lovett , J. H. Jefferson , G. A. D. Briggs

According to quantum Zeno dynamics (QZD), the evolution of a quantum system can be restricted to a subspace of its Hilbert space by frequent measurements. A crucial question in QZD of a particle's position is: how short the time interval…

Quantum Physics · Physics 2025-10-01 Varqa Abyaneh , Parsa Ghorbani

In this study, we investigate the decoherence of a spatially superposed electrically neutral spin-$\frac12$ particle in the presence of a relativistic quantum electromagnetic field in Minkowski spacetime. We demonstrate that decoherence due…

Quantum Physics · Physics 2024-10-30 Kensuke Gallock-Yoshimura , Yuuki Sugiyama , Akira Matsumura , Kazuhiro Yamamoto

The quantum Zeno effect is well-known for fixing a system to an eigenstate by frequent measurements. It is also known that applying frequent unitary pulses induces a Zeno subspace that can also pin the system to an eigenspace. Both…

Quantum Physics · Physics 2021-09-13 Yi-Hsiang Chen

The time evolution of low energy spin states of a single molecular magnet in a local electric field is investigated. The decoherence of the driven single molecular magnet weakly coupled to a thermal bosonic environment is analyzed by the…

Quantum Physics · Physics 2012-08-09 Xiang Hao , Chen Liu , Shiqun Zhu

Strain-induced gradients of local electric fields in semiconductor quantum dots can couple to the quadrupole moments of nuclear spins. We develop a theory describing the influence of this quadrupolar coupling (QC) on the spin correlators of…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 N. A. Sinitsyn , Yan Li , S. A. Crooker , A. Saxena , D. L. Smith

We study the influence of a detector on the decay law of a quantum state whose "undisturbed" survival probability is purely exponential. In particular, we consider a detector with a finite energy band of detection, i.e. it interacts only…

Quantum Physics · Physics 2015-06-19 Francesco Giacosa , Giuseppe Pagliara

We consider a continuous measurement of a two-level system (double-dot) by weakly coupled detector (tunnel point contact nearby). While usual treatment leads to the gradual system decoherence due to the measurement, we show that the…

Quantum Physics · Physics 2007-05-23 Alexander N. Korotkov

Spin-orbit effects on electron-electron interaction are studied theoretically. The corrections to the Coulomb interaction of quantum well electrons induced by the spin-orbit coupling are derived. The developed theory is applied to calculate…

Mesoscale and Nanoscale Physics · Physics 2009-05-08 M. M. Glazov , V. D. Kulakovskii

We describe a new approach to spin squeezing based on a double-pass Faraday interaction between an optical probe and an optically dense atomic sample. A quantum eraser is used to remove residual spin-probe entanglement, thereby realizing a…

Quantum Physics · Physics 2013-05-29 Collin M. Trail , Poul S. Jessen , Ivan H. Deutsch

We show experimentally how quantum interference can be produced using an integrated quantum system comprising an arch-shaped short quantum wire (or quantum point contact, QPC) of 1D electrons and a reflector forming an electronic cavity. On…

Mesoscale and Nanoscale Physics · Physics 2017-08-21 Chengyu Yan , Sanjeev Kumar , Michael Pepper , Patrick See , Ian Farrer , David Ritchie , Jonathan Griffiths , Geraint Jones

Frequent Measurements on an unstable particle located at observable initial state freeze the particle on this state, known as quantum Zeno effect [1-14]. Measurements on an observable subspace further open the prelude of quantum Zeno…

Quantum Physics · Physics 2017-02-03 Tung-Ho Shieh , Kun-Yuan Wu , Hsiu-Fen Kao , Kuan-Ming Hung

Different approaches in quantifying environmentally-induced decoherence are considered. We identify a measure of decoherence, derived from the density matrix of the system of interest, that quantifies the environmentally induced error,…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Arkady Fedorov , Leonid Fedichkin , Vladimir Privman

Continuous and pulsed quantum Zeno effects were observed using a $^{87}$Rb Bose-Einstein condensate(BEC). Oscillations between two ground hyperfine states of a magnetically trapped condensate, externally driven at a transition rate…