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Mika Sillanpaa - One of the best experts on this subject based on the ideXlab platform.
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quantum mechanics free subsystem with Mechanical Oscillators
Science, 2021Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of continuous measurement of the position of an oscillator. We show how it is possible to measure an oscillator without quantum back-action of the measurement by constructing one effective oscillator from two physical Oscillators. We realize such a quantum mechanics-free subsystem using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum back-action by 8 decibels on both of them, obtaining a total noise within a factor of 2 of the full quantum limit. This facilitates the detection of weak forces and the generation and measurement of nonclassical motional states of the Oscillators. Moreover, we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity 1.4 decibels below the separability bound.
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gravitational forces between nonclassical Mechanical Oscillators
Physical review applied, 2021Co-Authors: Yulong Liu, Jay Mummery, Jingwei Zhou, Mika SillanpaaAbstract:Interfacing quantum mechanics and gravity is one of the great open questions in natural science. MicroMechanical Oscillators have been suggested as a plausible platform to carry out these experiments. We present an experimental design aiming at these goals, inspired by Schm\"ole et al. [Class. Quantum Grav. 33, 125031 (2016)]. Gold spheres weighing of the order of a milligram will be positioned on large silicon nitride membranes, which are spaced at submillimeter distances from each other. These mass-loaded membranes are Mechanical Oscillators that vibrate at about $2$ kHz frequencies in a drum mode. They are operated and measured by coupling to microwave cavities. First, we show that it is possible to measure the gravitational force between the Oscillators at deep cryogenic temperatures, where thermal Mechanical noise is strongly suppressed. We investigate the measurement of gravity when the positions of the gravitating masses exhibit significant quantum fluctuations, including preparation of the massive Oscillators in the ground state, or in a squeezed state. We also present a plausible scheme to realize an experiment where the two Oscillators are prepared in a two-mode squeezed motional quantum state that exhibits nonlocal quantum correlations and gravity at the same time. Although the gravity is classical, the experiment will pave the way for testing true quantum gravity in related experimental arrangements. In a proof-of-principle experiment, we operate a 1.7 mm diameter ${\mathrm{Si}}_{3}{\mathrm{N}}_{4}$ membrane loaded by a 1.3 mg gold sphere. At a temperature of 10 mK, we observe the drum mode with a quality factor above half a million at 1.7 kHz, showing strong promise for the experiments. Following implementation of vibration isolation, cryogenic positioning, and phase noise filtering, we foresee that realizing the experiments is in reach by combining known pieces of current technology.
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quantum mechanics free subsystem with Mechanical Oscillators
arXiv: Quantum Physics, 2020Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of measurement of the position of an oscillator. The quantum noise associated with the measurement of a quadrature of the motion imprints a backaction on the orthogonal quadrature, which feeds back to the measured observable in the case of a continuous measurement. In a quantum backaction evading measurement, the added noise can be confined in the orthogonal quadrature. Here we show how it is possible to evade this limitation and measure an oscillator without backaction by constructing one effective oscillator from two physical Oscillators. This facilitates detection of weak forces and the creation and measurement of nonclassical motional states of the Oscillators. We realize the proposal using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum backaction by $8$ decibels on both of them, obtaining a total noise within a factor two from the full quantum limit. Moreover, by modifying the measurement we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity $1.3$ decibels below the separability bound.
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quantum mechanics free subsystem with Mechanical Oscillators
arXiv: Quantum Physics, 2020Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of continuous measurement of the position of an oscillator. Here we show how it is possible to measure an oscillator without quantum backaction of the measurement by constructing one effective oscillator from two physical Oscillators. We realize such a quantum-mechanics free subsystem using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum backaction by $8$ decibels on both of them, obtaining a total noise within a factor two of the full quantum limit. This facilitates detection of weak forces and the generation and measurement of nonclassical motional states of the Oscillators. Moreover, we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity $1.4$ decibels below the separability bound.
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prospects for observing gravitational forces between nonclassical Mechanical Oscillators
arXiv: Mesoscale and Nanoscale Physics, 2020Co-Authors: Yulong Liu, Jay Mummery, Mika SillanpaaAbstract:Interfacing quantum mechanics and gravity is one of the great open questions in natural science. MicroMechanical Oscillators have been suggested as a plausible platform to carry out these experiments. We present an experimental design aiming at these goals, inspired by Schm\"ole et al., Class. Quantum Grav. 33, 125031 (2016). Gold spheres weighing on the order a milligram will be positioned on large silicon nitride membranes, which are spaced at submillimeter distances from each other. These mass-loaded membranes are Mechanical Oscillators that vibrate at $\sim 2$ kHz frequencies in a drum mode. They are operated and measured by coupling to microwave cavities. First, we show that it is possible to measure the gravitational force between the Oscillators at deep cryogenic temperatures, where thermal Mechanical noise is strongly suppressed. We investigate the measurement of gravity when the positions of the gravitating masses exhibit significant quantum fluctuations, including preparation of the massive Oscillators in the ground state, or in a squeezed state. We also present a plausible scheme to realize an experiment where the two Oscillators are prepared in a two-mode squeezed motional quantum state that exhibits nonlocal quantum correlations and gravity the same time. Although the gravity is classical, the experiment will pave the way for testing true quantum gravity in related experimental arrangements. In a proof-of-principle experiment, we operate a 1.7 mm diameter Si$_3$N$_4$ membrane loaded by a 1.3 mg gold sphere. At 10 mK temperature, we observe the drum mode with a quality factor above half a million at 1.7 kHz, showing strong promise for the experiments. Following implementation of vibration isolation, cryogenic positioning, and phase noise filtering, we foresee that realizing the experiments is in reach by combining known pieces of current technology.
Matthew J Woolley - One of the best experts on this subject based on the ideXlab platform.
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quantum mechanics free subsystem with Mechanical Oscillators
Science, 2021Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of continuous measurement of the position of an oscillator. We show how it is possible to measure an oscillator without quantum back-action of the measurement by constructing one effective oscillator from two physical Oscillators. We realize such a quantum mechanics-free subsystem using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum back-action by 8 decibels on both of them, obtaining a total noise within a factor of 2 of the full quantum limit. This facilitates the detection of weak forces and the generation and measurement of nonclassical motional states of the Oscillators. Moreover, we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity 1.4 decibels below the separability bound.
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quantum mechanics free subsystem with Mechanical Oscillators
arXiv: Quantum Physics, 2020Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of measurement of the position of an oscillator. The quantum noise associated with the measurement of a quadrature of the motion imprints a backaction on the orthogonal quadrature, which feeds back to the measured observable in the case of a continuous measurement. In a quantum backaction evading measurement, the added noise can be confined in the orthogonal quadrature. Here we show how it is possible to evade this limitation and measure an oscillator without backaction by constructing one effective oscillator from two physical Oscillators. This facilitates detection of weak forces and the creation and measurement of nonclassical motional states of the Oscillators. We realize the proposal using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum backaction by $8$ decibels on both of them, obtaining a total noise within a factor two from the full quantum limit. Moreover, by modifying the measurement we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity $1.3$ decibels below the separability bound.
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quantum mechanics free subsystem with Mechanical Oscillators
arXiv: Quantum Physics, 2020Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of continuous measurement of the position of an oscillator. Here we show how it is possible to measure an oscillator without quantum backaction of the measurement by constructing one effective oscillator from two physical Oscillators. We realize such a quantum-mechanics free subsystem using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum backaction by $8$ decibels on both of them, obtaining a total noise within a factor two of the full quantum limit. This facilitates detection of weak forces and the generation and measurement of nonclassical motional states of the Oscillators. Moreover, we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity $1.4$ decibels below the separability bound.
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stabilized entanglement of massive Mechanical Oscillators
Nature, 2018Co-Authors: Caspar Ockeloenkorppi, Erno Damskagg, Juhamatti Pirkkalainen, A A Clerk, Francesco Massel, Matthew J Woolley, Muhammad Asjad, Mika SillanpaaAbstract:Quantum entanglement is a phenomenon whereby systems cannot be described independently of each other, even though they may be separated by an arbitrarily large distance 1 . Entanglement has a solid theoretical and experimental foundation and is the key resource behind many emerging quantum technologies, including quantum computation, cryptography and metrology. Entanglement has been demonstrated for microscopic-scale systems, such as those involving photons2–5, ions 6 and electron spins 7 , and more recently in microwave and electroMechanical devices8–10. For macroscopic-scale objects8–14, however, it is very vulnerable to environmental disturbances, and the creation and verification of entanglement of the centre-of-mass motion of macroscopic-scale objects remains an outstanding goal. Here we report such an experimental demonstration, with the moving bodies being two massive microMechanical Oscillators, each composed of about 10 12 atoms, coupled to a microwave-frequency electromagnetic cavity that is used to create and stabilize the entanglement of their centre-of-mass motion15–17. We infer the existence of entanglement in the steady state by combining measurements of correlated Mechanical fluctuations with an analysis of the microwaves emitted from the cavity. Our work qualitatively extends the range of entangled physical systems and has implications for quantum information processing, precision measurements and tests of the limits of quantum mechanics.
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entangled massive Mechanical Oscillators
arXiv: Mesoscale and Nanoscale Physics, 2017Co-Authors: Caspar Ockeloenkorppi, Erno Damskagg, Juhamatti Pirkkalainen, A A Clerk, Francesco Massel, Matthew J Woolley, Mika SillanpaaAbstract:An entangled quantum state of two or more particles or objects exhibits some of the most peculiar features of quantum mechanics. Entangled systems cannot be described independently of each other even though they may have an arbitrarily large spatial separation. Reconciling this property with the inherent uncertainty in quantum states is at the heart of some of the most famous debates in the development of quantum theory. Nonetheless, entanglement nowadays has a solid theoretical and experimental foundation, and it is the crucial resource behind many emerging quantum technologies. Entanglement has been demonstrated for microscopic systems, such as with photons, ions, and electron spins, and more recently in microwave and electroMechanical devices. For macroscopic objects, however, entanglement becomes exceedingly fragile towards environmental disturbances. A major outstanding goal has been to create and verify the entanglement between the motional states of slowly-moving massive objects. Here, we carry out such an experimental demonstration, with the moving bodies realized as two microMechanical Oscillators coupled to a microwave-frequency electromagnetic cavity that is used to create and stabilise the entanglement of the centre-of-mass motion of the Oscillators. We infer the existence of entanglement in the steady state by combining measurement of correlated Mechanical fluctuations with an analysis of the microwaves emitted from the cavity. Our work qualitatively extends the range of entangled physical systems, with implications in quantum information processing, precision measurement, and tests of the limits of quantum mechanics.
Caspar Ockeloenkorppi - One of the best experts on this subject based on the ideXlab platform.
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quantum mechanics free subsystem with Mechanical Oscillators
Science, 2021Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of continuous measurement of the position of an oscillator. We show how it is possible to measure an oscillator without quantum back-action of the measurement by constructing one effective oscillator from two physical Oscillators. We realize such a quantum mechanics-free subsystem using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum back-action by 8 decibels on both of them, obtaining a total noise within a factor of 2 of the full quantum limit. This facilitates the detection of weak forces and the generation and measurement of nonclassical motional states of the Oscillators. Moreover, we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity 1.4 decibels below the separability bound.
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quantum mechanics free subsystem with Mechanical Oscillators
arXiv: Quantum Physics, 2020Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of measurement of the position of an oscillator. The quantum noise associated with the measurement of a quadrature of the motion imprints a backaction on the orthogonal quadrature, which feeds back to the measured observable in the case of a continuous measurement. In a quantum backaction evading measurement, the added noise can be confined in the orthogonal quadrature. Here we show how it is possible to evade this limitation and measure an oscillator without backaction by constructing one effective oscillator from two physical Oscillators. This facilitates detection of weak forces and the creation and measurement of nonclassical motional states of the Oscillators. We realize the proposal using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum backaction by $8$ decibels on both of them, obtaining a total noise within a factor two from the full quantum limit. Moreover, by modifying the measurement we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity $1.3$ decibels below the separability bound.
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quantum mechanics free subsystem with Mechanical Oscillators
arXiv: Quantum Physics, 2020Co-Authors: Laure Mercier De Lepinay, Matthew J Woolley, Caspar Ockeloenkorppi, Mika SillanpaaAbstract:Quantum mechanics sets a limit for the precision of continuous measurement of the position of an oscillator. Here we show how it is possible to measure an oscillator without quantum backaction of the measurement by constructing one effective oscillator from two physical Oscillators. We realize such a quantum-mechanics free subsystem using two microMechanical Oscillators, and show the measurements of two collective quadratures while evading the quantum backaction by $8$ decibels on both of them, obtaining a total noise within a factor two of the full quantum limit. This facilitates detection of weak forces and the generation and measurement of nonclassical motional states of the Oscillators. Moreover, we directly verify the quantum entanglement of the two Oscillators by measuring the Duan quantity $1.4$ decibels below the separability bound.
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stabilized entanglement of massive Mechanical Oscillators
Nature, 2018Co-Authors: Caspar Ockeloenkorppi, Erno Damskagg, Juhamatti Pirkkalainen, A A Clerk, Francesco Massel, Matthew J Woolley, Muhammad Asjad, Mika SillanpaaAbstract:Quantum entanglement is a phenomenon whereby systems cannot be described independently of each other, even though they may be separated by an arbitrarily large distance 1 . Entanglement has a solid theoretical and experimental foundation and is the key resource behind many emerging quantum technologies, including quantum computation, cryptography and metrology. Entanglement has been demonstrated for microscopic-scale systems, such as those involving photons2–5, ions 6 and electron spins 7 , and more recently in microwave and electroMechanical devices8–10. For macroscopic-scale objects8–14, however, it is very vulnerable to environmental disturbances, and the creation and verification of entanglement of the centre-of-mass motion of macroscopic-scale objects remains an outstanding goal. Here we report such an experimental demonstration, with the moving bodies being two massive microMechanical Oscillators, each composed of about 10 12 atoms, coupled to a microwave-frequency electromagnetic cavity that is used to create and stabilize the entanglement of their centre-of-mass motion15–17. We infer the existence of entanglement in the steady state by combining measurements of correlated Mechanical fluctuations with an analysis of the microwaves emitted from the cavity. Our work qualitatively extends the range of entangled physical systems and has implications for quantum information processing, precision measurements and tests of the limits of quantum mechanics.
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entangled massive Mechanical Oscillators
arXiv: Mesoscale and Nanoscale Physics, 2017Co-Authors: Caspar Ockeloenkorppi, Erno Damskagg, Juhamatti Pirkkalainen, A A Clerk, Francesco Massel, Matthew J Woolley, Mika SillanpaaAbstract:An entangled quantum state of two or more particles or objects exhibits some of the most peculiar features of quantum mechanics. Entangled systems cannot be described independently of each other even though they may have an arbitrarily large spatial separation. Reconciling this property with the inherent uncertainty in quantum states is at the heart of some of the most famous debates in the development of quantum theory. Nonetheless, entanglement nowadays has a solid theoretical and experimental foundation, and it is the crucial resource behind many emerging quantum technologies. Entanglement has been demonstrated for microscopic systems, such as with photons, ions, and electron spins, and more recently in microwave and electroMechanical devices. For macroscopic objects, however, entanglement becomes exceedingly fragile towards environmental disturbances. A major outstanding goal has been to create and verify the entanglement between the motional states of slowly-moving massive objects. Here, we carry out such an experimental demonstration, with the moving bodies realized as two microMechanical Oscillators coupled to a microwave-frequency electromagnetic cavity that is used to create and stabilise the entanglement of the centre-of-mass motion of the Oscillators. We infer the existence of entanglement in the steady state by combining measurement of correlated Mechanical fluctuations with an analysis of the microwaves emitted from the cavity. Our work qualitatively extends the range of entangled physical systems, with implications in quantum information processing, precision measurement, and tests of the limits of quantum mechanics.
Huatang Tan - One of the best experts on this subject based on the ideXlab platform.
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deterministic quantum superpositions and fock states of Mechanical Oscillators via quantum interference in single photon cavity optomechanics
Physical Review A, 2014Co-Authors: Huatang TanAbstract:In this paper, we propose a scheme for deterministically preparing a quantum superposition $|{\ensuremath{\psi}}_{s}{\ensuremath{\rangle}}_{b}={C}_{0}{|0\ensuremath{\rangle}}_{b}+{C}_{\mathcal{N}}{|\mathcal{N}\ensuremath{\rangle}}_{b}$ between vacuum and an arbitrary Fock state ${|\mathcal{N}\ensuremath{\rangle}}_{b}$ of Mechanical Oscillators via strong single-photon optoMechanical coupling. We consider an optoMechanical cavity which contains a Kerr medium and is driven by two lasers, with one laser tuned to the cavity resonance and the other to the $\mathcal{N}$th lower sideband of the cavity. The amplitudes ${C}_{0}$ and ${C}_{\mathcal{N}}$ are determined only by the drive strengths in the absence of Mechanical damping and the approximate Fock state $|{\ensuremath{\psi}}_{s}{\ensuremath{\rangle}}_{b}\ensuremath{\approx}{|\mathcal{N}\ensuremath{\rangle}}_{b}$ can be obtained with appropriate relative strengths of the lasers. It is revealed that the superposition results from destructive quantum interference. The analytical results are confirmed by exact numerical calculation, and it is also shown that the nonclassical state is robust against thermal Mechanical noise.
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Single-atom quantum control of macroscopic Mechanical Oscillators
Physical Review A, 2014Co-Authors: Francesco Bariani, Johannes Otterbach, Huatang Tan, Pierre MeystreAbstract:We investigate a hybrid electro-Mechanical system consisting of a pair of charged macroscopic Mechanical Oscillators coupled to a small ensemble of Rydberg atoms. The resonant dipole-dipole coupling between an internal atomic Rydberg transition and the mechanics allows cooling to its motional ground state with a single atom despite the considerable mass imbalance between the two subsystems. We show that the rich electronic spectrum of Rydberg atoms, combined with their high degree of optical control, paves the way towards implementing various quantum-control protocol for the Mechanical Oscillators.
Radim Filip - One of the best experts on this subject based on the ideXlab platform.
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pulsed quantum interaction between two distant Mechanical Oscillators
Physical Review A, 2016Co-Authors: Nikita Vostrosablin, Andrey A Rakhubovsky, Radim FilipAbstract:Feasible setup for pulsed quantum nondemolition interaction between two distant Mechanical Oscillators through an optical or microwave mediator is proposed. The proposal uses homodyne measurement of the mediator and feedforward control of the Mechanical Oscillators to reach the interaction. To verify the quantum nature of the interaction, we investigate the Gaussian entanglement generated in the Mechanical modes. We evaluate it under influence of Mechanical bath and propagation loss for the mediator and propose ways to optimize the interaction. Finally, both currently available optoMechanical and electroMechanical platforms are numerically analyzed. The analysis shows that implementation is already feasible with current technology.
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deterministic nonclassicality for quantum Mechanical Oscillators in thermal states
Physical Review A, 2016Co-Authors: Petr Marek, Lukas Lachman, L Slodicka, Radim FilipAbstract:Quantum nonclassicality is the basic building stone for the vast majority of quantum information applications and methods of its generation are at the forefront of research. One of the obstacles any method needs to clear is the looming presence of decohorence and noise which act against the nonclassicality and often erase it completely. In this paper we show that nonclassical states of a quantum harmonic Oscillators initially in thermal equilibrium states can be deterministically created by coupling it to a single two level system. This can be achieved even in the absorption regime in which the two level system is initially in the ground state. The method is resilient to noise and it may actually benefit from it, as witnessed by the systems with higher thermal energy producing more nonclassical states.