Publications (27)
Force sensing in an optomechanical system with feedback-controlled in-loop light
F. Bemani, O. ÄernotÃk, L. Ruppert +2
Quantum control techniques applied at macroscopic scales provide us with opportunities in fundamental physics and practical applications. Among them, measurement-based feedback all…
How quantum correlations enhance prediction of complementary measurements
R. Filip, M. Gavenda, J. Soubusta +2
If there are correlations between two qubits then the results of the measurement on one of them can help to predict measurement results on the other one. It is an interesting quest…
Generation of ideal thermal light in warm atomic vapor
J. Mika, L. Podhora, L. Lachman +5
We present the experimental generation of light with directly observable close-to ideal thermal statistical properties. The thermal light state is prepared using a spontaneous Rama…
Quantum Filtering of Optical Coherent States
C. Wittmann, D. Elser, U. L. Andersen +3
We propose and experimentally demonstrate non-destructive and noiseless removal (filtering) of vacuum states from an arbitrary set of coherent states of continuous variable systems…
Separating the classical and quantum information via quantum cloning
M. Ricci, F. Sciarrino, N. J. Cerf +3
An application of quantum cloning to optimally interface a quantum system with a classical observer is presented, in particular we describe a procedure to perform a minimal disturb…
Unconditional accumulation of nonclassicality in a single-atom mechanical oscillator
L. Podhora, T. Pham, A. Lešundák +6
We report on the robust experimental accumulation of nonclassicallity of motion of a single trapped ion. The nonclassicality stems from deterministic incoherent modulation of therm…
Non-perturbative solution of nonlinear Heisenberg equations
L. Mista, R. Filip
A new non-perturbative method of solution of the nonlinear Heisenberg equations in the finite-dimensional subspace is illustrated. The method, being a counterpart of the traditiona…
Quantum controlled-Z gate for weakly interacting qubits
M. Micuda, R. Starek, I. Straka +5
We propose and experimentally demonstrate a scheme for implementation of a maximally entangling quantum controlled-Z gate between two weakly interacting systems. We conditionally e…
Experimental realization of a minimal disturbance quantum measurement
F. Sciarrino, M. Ricci, F. De Martini +2
We report the first experimental realization of an ''optimal'' quantum device able to perform a Minimal Disturbance Measurement (MDM) on polarization encoded qubits saturating the…
Squeezed state purification with linear optics and feed forward
O. Glöckl, U. L. Andersen, R. Filip +2
A scheme for optimal and deterministic linear optical purification of mixed squeezed Gaussian states is proposed and experimentally demonstrated. The scheme requires only linear op…
Experimental distillation of squeezing from non-Gaussian quantum states
J. Heersink, Ch. Marquardt, R. Dong +4
We show theoretically and experimentally that single copy distillation of squeezing from continuous variable non-Gaussian states is possible using linear optics and conditional hom…
Work and information from thermal states after subtraction of energy quanta
J. Hloušek, M. Ježek, R. Filip
Quantum oscillators prepared out of thermal equilibrium can be used to produce work and transmit information. By intensive cooling of a single oscillator, its thermal energy determ…
Extracting work from quantum states of radiation
M. KoláÅ, A. Ryabov, R. Filip
Quantum optomechanics opens a possibility to mediate a physical connection of quantum optics and classical thermodynamics. We propose and theoretically analyze a one-way chain star…
Control and enhancement of interferometric coupling between two photonic qubits
R. Stárek, M. MiÄuda, I. Straka +4
We theoretically investigate and experimentally demonstrate a procedure for conditional control and enhancement of an interferometric coupling between two qubits encoded into state…
Characterization of Linear Measurements in Cavity Optomechanics: Examples and Applications
F. Bemani, O. ÄernotÃk, R. Filip
Detailed understanding of physical measurements is essential for devising efficient metrological strategies and measurement-feedback schemes, as well as finding fundamental limitat…
Experimental test of strongly non-classical character of a noisy squeezed single-photon state
M. Jezek, A. Tipsmark, R. Dong +4
We experimentally verify the quantum non-Gaussian character of a conditionally generated noisy squeezed single-photon state with positive Wigner function. Employing an optimized wi…
Reversibility of continuous-variable quantum cloning
R. Filip, J. Fiurasek, P. Marek
We analyze a reversibility of optimal Gaussian quantum cloning of a coherent state using only local operations on the clones and classical communication between them and p…
Multipartite Asymmetric Quantum Cloning
S. Iblisdir, A. Acin, N. Gisin +3
We investigate the optimal distribution of quantum information over multipartite systems in asymmetric settings. We introduce cloning transformations that take identical replic…
Quantum non-Gaussian coherences of an oscillating atom
A. Kovalenko, L. Lachman, T. Pham +4
Quantum coherence between energy eigenstates of harmonic oscillators is essential for quantum physics. Even the most elementary binary superpositions of the ground and the higher e…
Heralded quantum non-Gaussian states in pulsed levitating optomechanics
F. Bemani, A. A. Rakhubovsky, R. Filip
Optomechanics with levitated nanoparticles is a promising way to combine very different types of quantum non-Gaussian aspects induced by continuous dynamics in a nonlinear or time-…
Emergence of super-Poissonian light from indistinguishable single-photon emitters
A. Kovalenko, D. Babjak, A. Lešundák +7
The optical interference constitutes a paramount resource in modern physics. At the scale of individual atoms and photons, it is a diverse concept that causes different coherent ph…
Knowledge excess duality and violation of Bell inequalities
R. Filip, M. Gavenda
A constraint on two complementary knowledge excesses by maximal violation of Bell inequalities for a single copy of any mixed state of two qubits is analyzed. The complementa…
Slowing Quantum Decoherence by Squeezing in Phase Space
H. Le Jeannic, A. Cavaillès, K. Huang +2
Non-Gaussian states, and specifically the paradigmatic Schrödinger cat state, are well-known to be very sensitive to losses. When propagating through damping channels, these state…
Experimental Fock-State Bunching Capability of Non-Ideal Single-Photon States
P. Zapletal, T. Darras, H. Le Jeannic +4
Advanced quantum technologies, as well as fundamental tests of quantum physics, crucially require the interference of multiple single photons in linear-optics circuits. This interf…
Violation of Bell's inequalities with pre-amplified homodyne detection
G. Torlai, G. McKeown, P. Marek +4
We show that the use of probabilistic noiseless amplification in entangled coherent state-based schemes for the test of quantum non locality provides substantial advantages. The th…
Optical synthesis of large-amplitude squeezed coherent-state superpositions with minimal resources
K. Huang, H. Le Jeannic, J. Ruaudel +10
We propose and experimentally realize a novel versatile protocol that allows the quantum state engineering of heralded optical coherent-state superpositions. This scheme relies on…
Experimental Purification of Single Qubits
M. Ricci, F. De Martini, N. J. Cerf +3
We report the experimental realization of the purification protocol for single qubits sent through a depolarization channel. The qubits are associated with polarization encoded pho…