English
Related papers

Related papers: Continuous-variable two-dimensional cluster states…

200 papers

We demonstrate that the confinement of half-quantized vortices (HQVs) in coherently coupled Bose-Einstein condensates (BECs) simulates certain aspects of the confinement in $SU(2)$ quantum chromodynamics (QCD) in 2+1 space-time dimensions.…

Quantum Gases · Physics 2018-02-14 Minoru Eto , Muneto Nitta

Quantum metrology utilizes nonclassical states to improve the precision of measurement devices. In this context, strongly squeezed vacuum states of light have proven to be a useful resource. They are typically produced by spontaneous…

Instantaneous quantum computing is a sub-universal quantum complexity class, whose circuits have proven to be hard to simulate classically in the Discrete-Variable (DV) realm. We extend this proof to the Continuous-Variable (CV) domain by…

Quantum Physics · Physics 2017-02-21 T. Douce , D. Markham , E. Kashefi , E. Diamanti , T. Coudreau , P. Milman , P. van Loock , G. Ferrini

We study nonclassical correlations in propagating two-mode squeezed microwave states in the presence of noise. We focus on two different types of correlations, namely, quantum entanglement and quantum discord. Quantum discord has various…

We experimentally realize "hybrid" entanglement swapping between discrete-variable (DV) and continuous-variable (CV) optical systems. DV two-mode entanglement as obtainable from a single photon split at a beam splitter is robustly…

Quantum Physics · Physics 2015-06-23 Shuntaro Takeda , Maria Fuwa , Peter van Loock , Akira Furusawa

Theoretical analysis is given for a two-photon subtraction from a continuous wave (CW) squeezed vacuum with finite time separation between two detection events. In the CW photon subtraction process, the generated states are inevitably…

Quantum Physics · Physics 2009-11-13 Masahiro Takeoka , Hiroki Takahashi , Masahide Sasaki

We demonstrate experimentally how to remove an arbitrary node from a continuous-variable cluster state and how to shorten any quantum wires of such a state. These two basic operations, performed in an unconditional fashion, are a…

We report detailed investigation of the existence and stability of mixed and demixed modes in binary atomic Bose-Einstein condensates with repulsive interactions in a ring-trap geometry. The stability of such states is examined through…

Quantum Gases · Physics 2019-09-04 Zhaopin Chen , Yongyao Li , Nikolaos P. Proukakis , Boris A. Malomed

Multidimensional cluster states are a key resource for robust quantum communication, measurement-based quantum computing and quantum metrology. Here, we present a device capable of emitting large-scale entangled microwave photonic states in…

We explore optical quantum engineering of phase-parameterized continuous-variable (CV) probe states to exploit nonclassical light to solve the problem of precise phase estimation. The optical interferometer consists of a single beam…

Quantum Physics · Physics 2026-03-11 Mikhail S. Podoshvedov , Sergey A. Podoshvedov

We theoretically investigate the role of different phases of coupling constants in the dynamics of atoms and two cavity modes, observing deterministic generation of prototype or hybrid Bell, W, GHZ, and cluster states. Commonly induced…

Quantum Physics · Physics 2015-03-17 P. P. Munhoz , F. L. Semião

The size of the Hilbert space for a multiqubit state scales exponentially with the number of constituent qubits. Often this leads to a similar exponential scaling of the experimental resources required to characterize the state. Contrary to…

Quantum Physics · Physics 2024-05-06 Konstantin Tiurev , Anders S. Sørensen

We present a first-principles theoretical analysis of the entanglement of two superconducting qubits in spatially separated microwave cavities by a sequential (cascaded) probe of the two cavities with a coherent mode, that provides a full…

Quantum Physics · Physics 2016-10-25 Felix Motzoi , K. Birgitta Whaley , Mohan Sarovar

Harnessing quantum mechanics properties, quantum computers have the potential to outperform classical computers in many applications and are envisioned to affect various aspects of our society. Different approaches are being explored for…

Quantum Physics · Physics 2025-07-02 Muhammad Kashif , Saif Al-Kuwari

Continuous-variable quantum key distribution (CV-QKD) is realized with coherent detection and is therefore very suitable for a cost-efficient implementation. The major challenge in CV-QKD is mitigation of laser phase noise at a signal to…

Quantum Physics · Physics 2019-08-13 Sebastian Kleis , Max Rueckmann , Christian G. Schaeffer

We theoretically investigate the creation of squeezed states of a Bose-Einstein Condensate (BEC) trapped in a magnetic double well potential. The number or phase squeezed states are created by modulating the tunnel coupling between the two…

Quantum Physics · Physics 2017-12-13 Georg Jäger , Tarik Berrada , Jörg Schmiedmayer , Thorsten Schumm , Ulrich Hohenester

In the current quest for efficient and experimentally feasible platforms for implementation of multimode squeezing and entanglement in the continuous variable regime, we underpin and complement our results on the generation of versatile…

Continuous variable encoding of quantum information requires the deterministic generation of highly correlated quantum states of light in the form of quantum networks, which, in turn, necessitates the controlled generation of a large number…

Traditional method for measuring continuous-variable quantum entanglement relies on balanced homodyne detections, which are sensitive to vacuum quantum noise coupled in through losses resulted from many factors such as detector's quantum…

Quantum Physics · Physics 2020-05-06 Jiamin Li , Yuhong Liu , Nan Huo , Liang Cui , Sheng Feng , Xiaoying Li , Z. Y. Ou

Two-mode squeezed states, which are entangled states with bipartite quantum correlations in continuous-variable systems, are crucial in quantum information processing and metrology. Recently, continuous-variable quantum computing with the…

Quantum Physics · Physics 2023-11-10 Wui Seng Leong , Mingjie Xin , Zilong Chen , Yu Wang , Shau-Yu Lan