Vectorial polaritons in the quantum motion of a levitated nanosphere

Ranfagni, A.; Vezio, P.; Calamai, M.; Chowdhury, Avishek; Marino, Francesco; Marín, F.

doi:10.1038/s41567-021-01307-y

Cited by 27 publications

(18 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…( 8) coincide with the Γ d j . The calculated fluctuations due to the laser intensity and frequency noise are indeed negligible [20], and the measured decoherence rate shows that even parametric heating due to mechanical vibrations, whose relevance was pointed out in other works [12,13], do not play an evident role in our case. We also remark that we can distinguish the dipole scattering rates in the two modes, whose ratio (weakly dependent on the detection efficiency) we find to be a X /a Y = 1.42 ± 0.14.…”

Section: Measurement Of the Decoherence Ratessupporting

confidence: 66%

“…We note that the experiment at varying polarization angle was performed with a different nanosphere with respect to the previously described experiences, and g max is now slightly larger. The system is now in the 2D, coherent strong coupling regime [20]. The peak originating from the dark mode is broadened, showing that the cooling is indeed efficient in the whole X − Y plane.…”

Section: For a Detuning ∆mentioning

confidence: 95%

“…−Ω X,Y the optomechanical effect is maximum and the bright mode is strongly coupled with the optical field, yielding hybridized modes (polaritons) [20,34]. An example of the heterodyne spectrum is shown in Fig.…”

Section: For a Detuning ∆mentioning

confidence: 99%

“…In any other direction of the plane, the motion is given by a weighted sum of the two oscillations, with a spectrum displaying two peaks, and it cannot be simply reproduced by a single harmonic oscillator. Introducing the strong coupling with the cavity field, the system is generally described by three harmonic oscillators associated to the hybridized modes (vectorial polaritons [20]), defined by the eigenvectors of the drift matrix. Therefore, in this case, in no direction can the motion be simply associated to a single harmonic oscillator.…”

Section: For a Detuning ∆mentioning

confidence: 99%

“…The problem is theoretically analyzed in [19] where it is shown that for suitable system parameters the particle full planar motion can be strongly coupled to the light and efficiently cooled through coherent scattering. Recently, the quantum-coherent strong coupling between the 2D motion of a levitating nanoparticle and the radiation field has been demonstrated, and led to the observation of vectorial optomechanical polaritons [20]. Nevertheless, the ground state of the 2D motion has never been approached so far.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Two-dimensional quantum motion of a levitated nanosphere

Ranfagni,

Børkje,

Marino

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

We report on the two-dimensional (2D) dynamics of a levitated nanoparticle in an optical cavity. The motion of the nanosphere is strongly coupled to the cavity field by coherent scattering and heavily cooled in the plane orthogonal to the tweezer axis. Due to the characteristics of the 2D motion and the strong optomechanical coupling, the motional sideband asymmetry that reveals the quantum nature of the dynamics is not limited to mere scale factors between Stokes and anti-Stokes peaks, as customary in quantum optomechanics, but assumes a peculiar spectral dependence. We introduce and discuss an effective thermal occupancy that quantifies how close the system is to a minimum uncertainty state and allows us to consistently characterize the particle motion. By rotating the polarization angle of the tweezer beam we tune the system from a one-dimensional (1D) cooling regime, where we achieve a best thermal occupancy of 0.51 ± 0.05, to a regime in which the fully 2D dynamics of the particle exhibits strong non-classical properties. We achieve a strong 2D confinement with thermal occupancy of 3.4 ± 0.4 along the warmest direction and around unity in the orthogonal one. These results represents a major improvement with respect to previous ex-

show abstract

Section: Measurement Of the Decoherence Ratessupporting

confidence: 66%

Section: For a Detuning ∆mentioning

confidence: 95%

Section: For a Detuning ∆mentioning

confidence: 99%

Section: For a Detuning ∆mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Two-dimensional quantum motion of a levitated nanosphere

Ranfagni,

Børkje,

Marino

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

Brownian Fluctuations of a non-confining potential

Melo,

Paraguassú,

Nascimento

et al. 2024

Physica A: Statistical Mechanics and its Applications

View full text Add to dashboard Cite

Inert Shell Coating for Enhanced Laser Refrigeration of Nanoparticles: Application in Levitated Optomechanics

Laplane,

Ren,

Roberts

et al. 2024

ACS Photonics

View full text Add to dashboard Cite

Levitated nanoparticles in vacuum, with their intrinsically low coupling to the environment, hold the promise of precision force sensing and open new avenues for exploring macroscopic quantum physics. Ultimately, the coherence of the levitated oscillator is limited by its blackbody radiation emission and hence its internal temperature. Controlling the internal temperature of a levitated object in vacuum poses a formidable challenge, necessitating contactless cooling methods such as laser refrigeration via anti-Stokes fluorescence. We report on a study exploring the design and synthesis of nanoparticles that can enhance their laser refrigeration efficiency. We developed lanthanide-doped nanocrystals with an inert shell coating and compared their cooling performance with that of bare nanocrystals while optically levitated. We found that the core–shell design shows an improvement in the minimum final temperature: about 31% of the core–shell nanoparticles showed significant cooling compared to a minimal cooling effect for 12% of the bare nanoparticles. Furthermore, we measured a core–shell nanoparticle cooling down to a temperature of 148 ± 4 K at 26 mbar in the underdamped regime. Our study is a first step toward engineering nanoparticles that are suitable for achieving absolute (center of mass and internal temperature) cooling in levitation, enabling novel prospects for realizing macroscopic quantum superpositions.

show abstract

Vectorial polaritons in the quantum motion of a levitated nanosphere

Cited by 27 publications

References 58 publications

Two-dimensional quantum motion of a levitated nanosphere

Two-dimensional quantum motion of a levitated nanosphere

Brownian Fluctuations of a non-confining potential

Inert Shell Coating for Enhanced Laser Refrigeration of Nanoparticles: Application in Levitated Optomechanics

Contact Info

Product

Resources

About