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A quarter century of progress in holographic optical trapping has yielded fundamental advances in the science of classical wave-matter interactions. These efforts have drawn attention to the connection between wavefront topology and wave-mediated forces, including the interrelated roles of orbital and spin angular momentum, and the interplay between conservative intensity-gradient forces and non-conservative phase-gradient forces. Holographically structured force landscapes can act as knots, micromachines and even tractor beams and have permeated application areas ranging from biomedical research to quantum computing. Lessons learned from holographic optical trapping recently have been applied to acoustic micromanipulation, with remarkable effect. Beyond an overall leap in the force scales that can be achieved with sound, advances in acoustic trapping are casting new light on the nature of wave-matter interactions, including the role of nonreciprocal wave-mediated interactions in creating novel states of organization. 

The similarity between the 2D Helmholtz equation in elliptical coordinates and the Schr¨odinger equation for the simple mechanical pendulum inspires us to use light to mimic this quantum system. When optical beams are prepared in Mathieu modes, their intensity in the Fourier plane is proportional to the quantum mechanical probability for the pendulum. Previous works have produced a two-dimensional pendulum beam that oscillates as a function of time through the superpositions of Mathieu modes with phases proportional to pendulum energies. Here we create a three-dimensional pendulum wavepacket made of a superposition of Helical Mathieu-Gaussian modes, prepared in such a way that the components of the wave-vectors along the propagation direction are proportional to the pendulum energies. The resulting pattern oscillates or rotates as it propagates, in 3D, with the propagation coordinate playing the role of time. We obtained several different propagating beam patterns for the unbound-rotor and the bound-swinging pendulum cases. We measured the beam intensity as a function of the propagation distance. The integrated beam intensity along elliptical angles plays the role of quantum pendulum probabilities. Our measurements are in excellent agreement with numerical simulations. 

When situations make it diffcult for students to be physically present in the laboratory, there is a need to provide remote instructional offerings. This is a particularly acute problem in upper-level physics laboratories because they involve the use of sophisticated equipment for the investigation of advanced topics. The possibility of automating such experiences presents itself as a possible solution. In this article I present the offering of an automated quantum optics lab for advanced physics students. I do so by automating the laboratory components via actuators and sensors controlled through serial connections. Live images of the laboratory provide visual inspection of the apparatus and sensors. All of these components are connected to a personal computer that students can control by remote access. The experience provides a new paradigm for experimentation, giving students experience on laboratory work with a remote apparatus at fexible times, making the experiment a form of homework assignment. 

We use a spatial light modulator (SLM) to mimic the e ect of gravity and steer the light from a laser to observe Einstein rings with a laboratory camera. The derived programming of the phase of the SLM follows a logarithmic dependence with impact parameter. As expected, we also observe arcs when the source and lensing object are not in line with the observer. Measurements for distinct parameters are consistent with the expectations. The coherent optical beams that are programmed to follow gravitational lensing trajectories have a transverse mode consistent with Bessel functions, yet they do not exhibit the non-di racting properties of Bessel beams: they expand linearly with the propagation distance. The addition of a vortex phase also produces patterns that coincide with Bessel modes of order given by the topological charge of the vortex.