A microsphere molecule: The interaction of two charged microspheres in a magneto-gravitational trap

Abstract

Optomechanical systems composed of levitated particles in vacuum provide excellent conditions to test the predictions of both classical and quantum physics. While similar in approach, differing experimental setups used to achieve levitation and trapping provide unique parameter regimes for study. In this work, we show that the highly anisotropic and deep potential well provided by a magnetogravitational trap allows the creation of a micrometer-scale “molecule” consisting of two like-charged microspheres in a harmonic potential. We demonstrate the detection and manipulation (excitation and cooling) of two distinct modes of the microsphere molecule motion along the weakest trap axis.

Sympathetic cooling and squeezing of two co-levitated nanoparticles

“…By implementing a velocity damping scheme [30][31][32][33][34][35][36][37][38] on just one particle we sympathetically cool the motion of the second particle to achieve sub-kelvin normal mode temperatures. This differs from previous work [12] were both particles were cooled simultaneously. Importantly, we also show that the Coulomb interaction can transfer other states between co-trapped particles by squeezing the normal mode of the system with a parametric drive [26,27,[39][40][41][42][43][44] on just one particle.…”

“…They have already been been used in the search for dark matter candidates [1][2][3], for investigating the macroscopic limits of quantum mechanics [4][5][6][7] and measuring short-range forces [7][8][9][10]. To date, only a few investigations have focused on cooling and controlling more than a single particle levitated in vacuum [11,12]. Arrays of levitated nanoparticles are of interest as they can be used to enhance detection of dark matter candidates [2,3], measure vacuum friction [13] and even for evdiencing quantumness of gravity via entanglement [14,15].…”

“…It is made possible by the strong coupling from the Coulomb interaction between co-trapped ions. Coupling between two levitated nanoparticles in vacuum has been demonstrated with optical binding [11] and via the Coulomb interaction [12]. The ability to cool and control all particles via a single particle using light, while not illuminating the other co-trapped particles, can be used to minimise heating [22,23], particularly when they contain internal atomic like systems such as nitrogen vacancy centers, whose internal state manipulation is highly temperature dependent.…”

Observation of strong and tunable light-induced dipole-dipole interactions between optically levitated nanoparticles

“…Engineered strong optical and electrostatic interactions between multiple macroscopic objects may open up many research avenues in quantum physics. We foresee that the platform described in this work -with a possible addition of an optical cavity -can be used for quantum simulation with mechanical degrees of freedom [54][55][56], enhanced quantum sensing [57], collective effects [28,58,59], (quantum) synchronization [60][61][62], studies of molecular structures [63], ultrastrong coupling between harmonic oscillators [64] or phonon transport and thermalization [30]…”

Quantum Information Processing and Precision Measurement Using a Levitated Nanodiamond

“…The levitated optomechanical array has been studied experimentally, [ 116,117 ] and the prethermalization and nonreciprocal phonon transport have been predicted theoretically in this system. [ 118 ] In future, it would be interesting to trap multiple nanodiamonds with embedded NV centers in an array of traps, and study the quantum information processing and quantum simulations in this system.…”