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Related papers: Entanglement Assisted Metrology

200 papers

Nuclear magnetic resonance (NMR) experiments can reveal local properties in materials, but are often limited by the low signal-to-noise ratio. Spin squeezed states have an improved resolution below the Heisenberg limit in one of the spin…

Single-qubit measurements are typically insufficient for inferring arbitrary quantum states of a multi-qubit system. We show that if the system can be fully controlled by driving a single qubit, then utilizing a local random pulse is almost…

Quantum Physics · Physics 2020-01-14 Pengcheng Yang , Min Yu , Ralf Betzholz , Christian Arenz , Jianming Cai

We investigate analytically and numerically the Multiple Quantum (MQ) NMR dynamics in systems of nuclear spins 1/2 coupled by the dipole-dipole interactions in the case of the dipolar ordered initial state. We suggest two different methods…

Other Condensed Matter · Physics 2009-11-13 S. I. Doronin , E. B. Fel'dman , E. I. Kuznetsova , G. B. Furman , S. D. Goren

In this work, we have been working on the concept of quantum entanglement. At first, we studied the theory of entanglement in its characterization and measurement, introducing a new scheme for detection of entanglement. The new approach…

Quantum Physics · Physics 2007-05-23 Robabeh Rahimi

We report entanglement of a single atom's hyperfine spin state with its motional state in a timescale of less than 3 ns. We engineer a short train of intense laser pulses to impart a spin-dependent momentum transfer of +/- 2 hbar k. Using…

Quantum Physics · Physics 2013-07-04 J. Mizrahi , C. Senko , B. Neyenhuis , K. G. Johnson , W. C. Campbell , C. W. S. Conover , C. Monroe

Spins in solids and molecules are promising for applications of quantum sensing technology. The sensitivity of the quantum sensing depends on how precisely spin observables can be determined in the measurement, and is intrinsically limited…

Quantum Physics · Physics 2025-11-21 Yifan Song , Nabiha Hasan , Susumu Takahashi

We report an electronic magnetization measurement of a quantum point contact (QPC) based on nuclear magnetic resonance (NMR) spectroscopy. We find that NMR signals can be detected by measuring the QPC conductance under in-plane magnetic…

Mesoscale and Nanoscale Physics · Physics 2015-07-16 Minoru Kawamura , Keiji Ono , Peter Stano , Kimitoshi Kono , Tomosuke Aono

We investigate the evolution of entanglement in multiple-quantum (MQ) NMR experiments in crystals with pairs of close nuclear spins-1/2. The initial thermodynamic equilibrium state of the system in a strong external magnetic field evolves…

Quantum Physics · Physics 2009-11-13 E. B. Fel'dman , A. N. Pyrkov

Measurement of quantum systems inevitably involves disturbance in various forms. Within the limits imposed by quantum mechanics, however, one can design an "ideal" projective measurement that does not introduce a back action on the measured…

Levitated macroscopic particles exhibiting quantum mechanical effects are garnering increased attention as a means for precision sensing and testing quantum mechanics. Defects in diamond, such as the nitrogen-vacancy (NV) centre possess…

Quantum Physics · Physics 2026-03-04 A. A. Wood , D. S. Rice , T. Xie , F. H. Cassells , R. M. Goldblatt , T. Delord , G. Hétet , A. M. Martin

The nuclear spin is a prime candidate for quantum information applications due to its weak coupling to the environment and inherently long coherence times. However, this weak coupling also challenges the addressability of the nuclear spin.…

Quantum Physics · Physics 2025-12-15 Hester G. Vennema , Cristina Mier , Evert W. Stolte , Leonard Edens , Jinwon Lee , Sander Otte

Interacting quantum systems are attracting increasing interest for developing precise metrology. In particular, the realisation that quantum-correlated states and the dynamics of interacting systems can lead to entirely new and unexpected…

Quantum Physics · Physics 2021-04-02 Min Jiang , Yunlan Ji , Qing Li , Ran Liu , Dieter Suter , Xinhua Peng

Entanglement is the quintessential quantum phenomenon and a necessary ingredient in most emerging quantum technologies, including quantum repeaters, quantum information processing (QIP) and the strongest forms of quantum cryptography. Spin…

Working with nuclear magnetic resonance (NMR) in quadrupolar spin systems, in this paper we transfer the concept of atomic coherent state to the nuclear spin context, where it is referred to as pseudo-nuclear spin coherent state…

Quantum Physics · Physics 2013-10-15 R. Auccaise , E. R. deAzevedo , E. I. Duzzioni , T. J. Bonagamba , M. H. Y. Moussa

The concept of entanglement, in which coherent quantum states become inextricably correlated, has evolved from one of the most startling and controversial outcomes of quantum mechanics to the enabling principle of emerging technologies such…

Entanglement plays a crucial role in proposals for quantum metrology, yet demonstrating quantum enhancement in sensing with sustained spin entanglement remains a challenging endeavor. Here, we combine optical pumping and continuous quantum…

Quantum Physics · Physics 2025-04-09 Junlei Duan , Zhiwei Hu , Xingda Lu , Liantuan Xiao , Suotang Jia , Klaus Mølmer , Yanhong Xiao

Single-spin detection is one of the important challenges facing the development of several new technologies, e.g. single-spin transistors and solid-state quantum computation. Magnetic resonance force microscopy with a cyclic adiabatic…

Spectroscopic measurements with low-temperature scanning tunneling microscopes have been used very successfully for studying not only individual atomic or molecular spins on surfaces but also complexly designed coupled systems. The symmetry…

Mesoscale and Nanoscale Physics · Physics 2017-03-28 Markus Ternes

The nuclear spins in nanostructured semiconductors play a central role in quantum applications. The nuclear spins represent a useful resource for generating local magnetic fields but nuclear spin noise represents a major source of dephasing…

Methods for achieving quantum control and detection of individual nuclear spins by single electrons of solid-state defects play a central role for quantum information processing and nano-scale nuclear magnetic resonance (NMR). However, with…

Quantum Physics · Physics 2017-03-06 Zhen-Yu Wang , Jorge Casanova , Martin B. Plenio