Related papers: High Q mg-scale monolithic pendulum for quantum-li…
Ultralow dissipation plays an important role in sensing applications and exploring macroscopic quantum phenomena using micro-and nano-mechanical systems. We report a diamagnetic-levitated micro-mechanical oscillator operating at a low…
Precise measurements of tiny forces and displacements play an important role in science and technology. The precision of recent experiments, while beginning to reach the limits imposed by quantum mechanics, is necessarily spoiled by the…
Commercial quartz oscillators of the tuning-fork type with a resonant frequency of ~32 kHz have been investigated in helium liquids. The oscillators are found to have at best Q values in the range 10^5-10^6, when measured in vacuum below…
A superconducting quantum magnetometer based on magnetic flux-driven modulation of the density of states of a proximized metallic nanowire is theoretically analyzed. With optimized geometrical and material parameters transfer functions up…
Quantum-dense metrology (QDM) constitutes a special case of quantum metrology in which two orthogonal phase space projections of a signal are simultaneously sensed beyond the shot noise limit. Previously it was shown that the additional…
Quantum non-demolition (QND) measurement enhances the detection efficiency and measurement fidelity, and is highly desired for its applications in precision measurements and quantum information processing. We propose and demonstrate a QND…
An ensemble of negatively charged nitrogen-vacancy centers in diamond can act as a precise quantum sensor even under ambient conditions. In particular, to optimize thier sensitivity, it is crucial to increase the number of spins sampled and…
We present the generation and detection of squeezed light in the 2 $\mathrm{\mu m}$ wavelength region. This experiment is a crucial step in realising the quantum noise reduction techniques that will be required for future generations of…
We investigate the feasibility of performing quantum non-demolition (QND) measurements in relativistic quantum systems, using the one-dimensional Dirac oscillator as a specific example. We derive general expressions for its QND observables…
Recently a protocol called quantum gravity induced entanglement of masses (QGEM) that aims to test the quantum nature of gravity using the entanglement of 2 qubits was proposed. The entanglement can arise only if the force between the two…
Recent spectacular results of gravitational waves obtained by the LIGO system, with frequencies in the 100 Hz regime, make corresponding laboratory experiments with full control over cause and effect of great importance. Dynamic…
A continuous quantum field, such as a propagating beam of light, may be characterized by a squeezing spectrum that is inhomogeneous in frequency. We point out that homodyne detectors, which are commonly employed to detect quantum squeezing,…
In traditional mechanics, harmonic oscillators can be used to measure force, acceleration, or rotation. Herein, we describe a quantum harmonic oscillator based on a penning trapped calcium ion crystal. Similar to traditional oscillators,…
We report the performance of a magnetically silent optically pumped cesium magnetometer with a statistical sensitivity of 3.5 pT/rtHz at 1~Hz and a stability of 90 fT over 150 seconds of measurement. Optical pumping with coherent,…
Phonons are envisioned as coherent intermediaries between different types of quantum systems. Engineered nanoscale devices such as optomechanical crystals (OMCs) provide a platform to utilize phonons as quantum information carriers. Here we…
Atom interferometry offers new perspectives for geophysics and inertial sensing. We present the industrial prototype of a new type of quantum-based instrument: a compact, transportable, differential quantum gravimeter capable of measuring…
We investigate the quantum signature of gravity in optomechanical systems under quantum control. We analyze the gravity-induced entanglement and squeezing in mechanical mirrors in a steady state. The behaviors and the conditions for…
We report low-temperature measurements of dissipation in megahertz-range, suspended, single-crystal nanomechanical oscillators. At millikelvin temperatures, both dissipation (inverse quality factor) and shift in the resonance frequency…
We describe a very stable type II optical parametric oscillator operated above threshold which provides 9.7 $\pm$ 0.5 dB (89%) of quantum noise reduction on the intensity difference of the signal and idler modes. We also report the first…
Characterization of noise of a quantum harmonic oscillator is important for many experimental platforms. We experimentally demonstrate motional spin-locking spectroscopy, a method that allows us to directly measure the motional noise…