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This paper analyses the cooling of a single particle in a harmonic trap with red-detuned laser light with fewer approximations than previously done in the literature. We avoid the adiabatic elimination of the excited atomic state but are still interested in Lamb-Dicke parameters η ≪ 1. Our results show that the Rabi frequency of the cooling laser can be chosen higher than previously assumed, thereby increasing the effective cooling rate but not affecting the final outcome of the cooling process. Since laser cooling is already a well established experimental technique, the main aim of this paper is to present a model which can be extended to more complex scenarios, like cavity-mediated laser cooling.

Cavity-mediated cooling has the potential to become one of the most efficient techniques to cool molecular species down to very low temperatures. In this paper we analyse cavity cooling with singlelaser driving for relatively large cavity decay rates κ and relatively large phonon frequencies ν. It is shown that cavity cooling and ordinary laser cooling are essentially the same within the validity range of the Lamb-Dicke approximation. This is done by deriving a closed set of rate equations and calculating the corresponding stationary state phonon number and cooling rate. For example, when ν is either much larger or much smaller than κ, the minimum stationary state phonon number scales as κ 2 /16ν 2 (strong confinement regime) and as κ/4ν (weak confinement regime), respectively.

The cooling rate for cavity-mediated laser cooling scales as the Lamb-Dicke parameter η squared. A proper analysis of the cooling process hence needs to take terms up to η 2 in the system dynamics into account. In this paper, we present such an analysis for a standard scenario of cavity-mediated laser cooling with η 1. Our results confirm that there are many similarities between ordinary and cavity-mediated laser cooling. However, for a weakly confined particle inside a strongly coupled cavity, which is the most interesting case for the cooling of molecules, numerical results indicate that more detailed calculations are needed to model the cooling process accurately.

Shave excision is a simple and cost-effective technique for the removal of suitable skin lesions. We performed a prospective study over six months, collecting data from pigmented lesions that were treated with shave excision by dermatologists. Only shave excisions with the intent to remove the lesion in toto were included. A total of 349 lesions were included in this study, 50 (14%) of these were melanomas and no melanoma diagnosed had deep margin involvement, while 13 (26%) had lateral margin involvement.