(E)-3-(2-Chloro-3,3,3-trifluoro­prop-1-en­yl)-2,2-dimethyl-N,N-diphenyl­cyclo­propane­carboxamide

The title compound, C21H19ClF3NO, was synthesized from 3-[(E)-2-chloro-3,3,3-trifluoro­prop-1-en­yl]-2,2-dimethyl­cyclo­propane­carboxylic acid and diphenyl­amine. The propenyl and carboxamide substituents lie on the same side of the cyclo­propane ring plane, with the two methyl substituents on either side of the plane. The phenyl rings of the carboxamide are inclined at an angle of 84.6 (3)° to one another. The F atoms are disordered over two positions; the site occupancy factors are ca 0.6 and 0.4

Cooling mechanical resonators to quantum ground state from room temperature

Ground-state cooling of mesoscopic mechanical resonators is a fundamental requirement for test of quantum theory and for implementation of quantum information. We analyze the cavity optomechanical cooling limits in the intermediate coupling regime, where the light-enhanced optomechanical coupling strength is comparable with the cavity decay rate. It is found that in this regime the cooling breaks through the limits in both the strong and weak coupling regimes. The lowest cooling limit is derived analytically at the optimal conditions of cavity decay rate and coupling strength. In essence, cooling to the quantum ground state requires $Q_{\mathrm{m}}>2.4n_{\mathrm{th}}$, with $Q_{\mathrm{m}}$ being the mechanical quality factor and $n_{\mathrm{th}}$ being the thermal phonon number. Remarkably, ground-state cooling is achievable starting from room temperature, when mechanical $Q$-frequency product $Q_{\mathrm{m}}{\nu>1.5}\times10^{13}$, and both of the cavity decay rate and the coupling strength exceed the thermal decoherence rate. Our study provides a general framework for optimizing the backaction cooling of mesoscopic mechanical resonators

(E)-3-(2-Chloro-3,3,3-trifluoro­prop-1-en­yl)-2,2-dimethyl-N-(2-naphth­yl)cyclo­propane­carboxamide

The title compound, C19H17ClF3NO, was synthesized from 3-[(E)-2-chloro-3,3,3-trifluoro­prop-1-en­yl]-2,2-dimethyl­cyclopropane­carboxylic acid and 2-aminona­phthalene. There are two molecules in the asymmetric unit. The dihedral angle between the naphthalene and cyclo­propane units is 111.6 (5)°. Molecules are connected into chains by intermol­ecular N—H⋯O hydrogen bonds. One of the Cl atoms is disordered over two positions with occupancies 0.653 (15) and 0.347 (15)