We are pleased to announce a monograph "DEVELOPMENT OF A HYBRID ATOMIC FORCE MICROSCOPE AND OPTICAL TWEEZERS APPARATUS" by Krzysztof Zembrzycki, Sylwia Pawłowska, Paweł Nakielski, Filippo Pierini (IPPT Reports 2/2016).

The role of mechanical properties is essential to understand molecular, biological materials and nanostructures dynamics and interaction processes. Atomic force microscopy (AFM), due to its sensitivity is the most commonly used method of direct force evaluation. Yet because of its technical limitations this single probe technique is unable to detect forces with femtonewton resolution. In this paper, we present the development of a combined atomic force microscopy and optical tweezers (AFM/OT) instrument. The system is based on a commercial AFM and confocal microscope. The addition of three lasers along with beam shaping and steering optics, on which the optical tweezer is based upon, provide us with the ability to manipulate small dielectric objects suspended in a fluid. Additionally, this same device allows for direct displacement and force measurement with very high resolution and accuracy in the same AFM scanning zone. We have also fitted a laser and a set of filters to observe fluorescent samples appropriately exited. We show that this is a great improvement of a standalone AFM force resolution and more so opens a way to conduct experiments using a hybrid double probe technique with high potential in nanomechanics, molecules manipulation and biological studies.

This study describes in detail the construction of all the modules such as the trapping laser optics, detection laser optics and the fluorescence module. Also, due to its importance on the performance of the equipment, the electronics part of the detection system is described. In the following chapters the whole adjustment and calibration is explained. The performance of the apparatus is fully characterized by studying the ability to trap dielectric objects and quantifying the detectable and applicable forces. The setting and sensitivity of the particle position detector and force sensor is shown. We additionally describe and compare different optical tweezer calibration methods. In the last part we show the ability of our instrument to conduct experiments using the proposed double-probe technique, in this case to study interaction forces between two particles.