English
Related papers

Related papers: Measuring the environment of a Cs qubit with dynam…

200 papers

Quantum bits or qubits naturally decohere by becoming entangled with uncontrollable environments. Dynamical decoupling is thereby required to disentangle qubits from an environment by periodically reversing the qubit bases, but this causes…

Quantum Physics · Physics 2020-02-26 Yuhei Sekiguchi , Yusuke Komura , Hideo Kosaka

We demonstrate a vapor cell atomic clock prototype based on continuous-wave (CW) interrogation and double-modulation coherent population trapping (DM-CPT) technique. The DM-CPT technique uses a synchronous modulation of polarization and…

Spectral characterization of noise environments that lead to the decoherence of qubits is critical to developing robust quantum technologies. While dynamical decoupling offers one of the most successful approaches to characterize noise…

Quantum Physics · Physics 2024-05-21 Arian Vezvaee , Nanako Shitara , Shuo Sun , Andrés Montoya-Castillo

A qubit can be used as a sensitive spectrum analyzer of its environment. Here we show how the problem of spectral analysis of noise induced by a strongly coupled environment can be solved for discrete spectra. Our analytical model shows…

Quantum Physics · Physics 2013-03-27 Shlomi Kotler , Nitzan Akerman , Yinnon Glickman , Roee Ozeri

We present a resource-efficient method based on repetitive weak measurements to directly measure the noise spectrum of a generic quantum environment that causes qubit phase decoherence. The weak measurement is induced by a Ramsey…

Quantum Physics · Physics 2026-01-27 Yuan-De Jin , Zheng-Fei Ye , Wen-Long Ma

Engineering entanglement between quantum systems often involves coupling through a bosonic mediator, which should be disentangled from the systems at the operation's end. The quality of such an operation is generally limited by…

The coherence time of an electron spin decohered by the nuclear spin environment in a quantum dot can be substantially increased by subjecting the electron to suitable dynamical decoupling sequences. We analyze the performance of high-level…

Mesoscale and Nanoscale Physics · Physics 2008-03-27 Wenxian Zhang , N. P. Konstantinidis , V. V. Dobrovitski , B. N. Harmon , Lea F. Santos , Lorenza Viola

Noise is possibly the most formidable challenge for quantum technologies. As such, a great deal of effort is dedicated to developing methods for noise reduction. One remarkable achievement in this direction is dynamical decoupling; it…

Quantum Physics · Physics 2024-06-28 Graeme D. Berk , Simon Milz , Felix A. Pollock , Kavan Modi

We introduce a novel method that we call Single-Shot Cross-Spectroscopy (SSCS), for extracting the auto- and cross-power spectral densities of dephasing noise of a qubit pair. The method uses straightforward input, namely single-shot…

Quantum Physics · Physics 2025-09-29 Juan S. Rojas-Arias , Peter Stano , Yi-Hsien Wu , Leon C. Camenzind , Seigo Tarucha , Daniel Loss

In this article, we study the dynamics of quantum correlation measures such as entanglement and measurement-induced nonlocality (MIN). Starting from an arbitrary Bell diagonal mixed states under Markovian local noise such as bit-phase flip,…

Quantum Physics · Physics 2021-06-09 S. Bhuvaneswari , R. Muthuganesan , R. Radha

We report the coherent manipulation of internal states of neutral atoms in a magnetic microchip trap. Coherence lifetimes exceeding 1 s are observed with atoms at distances of $5-130 \mu$m from the microchip surface. The coherence lifetime…

Quantum Physics · Physics 2009-11-10 Philipp Treutlein , Peter Hommelhoff , Tilo Steinmetz , Theodor W. Hänsch , Jakob Reichel

Aperiodic dynamical decoupling (DD) sequences of $\pi$ pulses are of great interest to decoherence control and have been recently extended from single-qubit to two-qubit systems. If the environmental noise power spectrum is made available,…

Quantum Physics · Physics 2011-10-25 Yu Pan , Zai-Rong Xi , Jiangbin Gong

We report on the immersion of a spin-qubit encoded in a single trapped ion into a spin-polarized neutral atom environment, which possesses both continuous (motional) and discrete (spin) degrees of freedom. The environment offers the…

Quantum Physics · Physics 2014-07-24 L. Ratschbacher , C. Sias , L. Carcagni , J. M. Silver , C. Zipkes , M. Köhl

We study resonance contrast by a two-step pulse observation method to enhance the frequency stability of coherent population trapping (CPT) atomic clocks. The proposed method is a two-step Raman--Ramsey scheme with low intensity during…

Atomic Physics · Physics 2017-03-08 Yuichiro Yano , Shigeyoshi Goka , Masatoshi Kajita

In this work, we investigate the dynamics of quantum correlations captured by entropic and geometric measures of discord under the influence of dissipative channels for widely used two qubit X state with maximally mixed marginals.…

Quantum Physics · Physics 2022-05-31 Nitish Kumar Chandra , Sarang S. Bhosale , Prasanta K. Panigrahi

We study the exact dynamics of optical qubits encoded via coherent states with opposite phases which are interacting with an environment modeled as a collection of simple harmonic oscillators. Making use of a coherent-state path integral…

Quantum Physics · Physics 2014-02-06 Ming-Jay Yang , Shin-Tza Wu

We experimentally demonstrate coherence recovery of singlet-triplet superpositions by interlacing qubit rotations between Carr-Purcell (CP) echo sequences. We then compare performance of Hahn, CP, concatenated dynamical decoupling (CDD) and…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 C. Barthel , J. Medford , C. M. Marcus , M. P. Hanson , A. C. Gossard

Many solid-state qubit systems are afflicted by low frequency noise mechanisms that operate along two perpendicular axes of the Bloch sphere. Depending on the qubit's control fields, either noise can be longitudinal or transverse to the…

Quantum Physics · Physics 2022-02-02 Guy Ramon , Łukasz Cywiński

We employ a continuous dynamical decoupling scheme to suppress the decoherence induced by elastic collisions of cold atoms. Using a continuous echo pulse we achieve a thirty-fold increase in the coherence time of Rb87 atoms trapped in a…

Quantum Physics · Physics 2009-05-28 Yoav Sagi , Ido Almog , Nir Davidson

It is generally assumed that environmental noise arising from thermal fluctuations is detrimental to preserving coherence and entanglement in a quantum system. In the simplest sense, dephasing and decoherence are tied to energy fluctuations…

Quantum Physics · Physics 2023-08-03 Eric R Bittner , Hao Li , Syad A. Shah , Carlos Silva , Andrei Piryatinski